1. Question Restatement
Are there other interpretive options for 1 John 5:2?
Any other interpretation would seem to require that we first redefine "loving God" and "His commandments" to mean something different than the meaning John has established in the minds of his readers thusfar.
Note: I do not see the merit in the arguments that the authors of the Gospel of John and 1 John are different. Regardless, the styles and suppositions of both writers are pretty much identical so comparative analysis can be reasonably made.
In the Gospel of John, the author explicitly, and repeatedly, redefines what the true commandments of God actually are, and what the true love of God actually is, (as all of the other New Testament writers do).
It would be a contradiction of the entire Gospel if it were to be supposed that the demonstration of love towards God is independent of the command to love unconditionally which is how Jesus loved.
So no: there probably isn't any other validly consistent interpretation of this text other than that the true demonstration of love towards God is indistinguishable from unconditional love towards others.
It is a huge misconception in Christianity that Jesus' commands were simply to love God and love others. The writer of 1 John is speaking of Jesus' commands - not tradition. Certainly, "loving God" and "loving others" are truly the greatest commandments OF THE LAW [of Moses], (Matthew 22-36-37), though not necessarily the greatest commandments OF ALL. Recall, Jesus was in debate with lawyers who were quite literally playing legal mind-games with him. And so, Jesus answered the specific question he was asked.
However, Jesus gave many, many, more commands emphasizing the necessity for "love in action", and not simply commanding people to "feel love". Even the expression "with all your heart" must be understood as "all your thoughts" - throughout all Scripture. Even those who don't personally feel love are nevertheless instructed to demonstrate God's own love towards the world.
1 John 3:23, NKJV - This is His commandment, that we believe in the name of His Son Jesus Christ, and love one another, just as [in the manner] He commanded us.
Note: This is not in the sense of, "and love one another according to what he commanded us". But rather, the writer is reminding to love in the manner that was described in great detail in the Passion narrative. Jesus' advocacy for the world, from a cross, was a demonstration his unconditional love.
But here is the "gotcha" - in John 13, Jesus issued a commandment even greater than Moses' version. Jesus issued a new commandment not given before which takes precedence over Moses' own, and therefore greater:
John 13:34, NKJV - A new commandment I give to you, that you love one another; as I have loved you, that you also love one another.
Christians were commanded to not merely love with all of their hearts, minds, souls, and strengths (which are woefully insufficient) - but to love instead with Jesus' heart, mind, soul, and strength. The love Jesus demonstrated for Christians to imitate was an unconditional love - where he advocated for everyone, unconditionally, even while be tortured to death by those same people.
NKJV, Luke 23:34 - Then Jesus said, “Father, forgive them, for they do not know what they do.” And they divided His garments and cast lots.
The Wisdom of God is not always "Just" because Wisdom never returns evil for evil but rather injects life wherever there is death. This is the unconditional love of Christ that Jesus commanded Christians to imitate. This is the heavenly precept, and temple, that Israel rejected at Sinai only to be replaced by a tabernacle and then with three temples that were made with mens' hands, while the blood of bulls and goats analogously fulfilled the obligation for the "unconditional" component of God's commandment.
It is the greatest misconception that it was Jesus' death that brought anyone life - for God never desired blood. But rather, it was Jesus' death that proved his unconditional love and advocacy - for life - that brought life.
NASB, John 14:15 - “If you love Me, you will keep My commandments.
Following Jesus' reasoning, there is therefore no distinction between unconditionally loving others as Jesus did and the demonstration of love towards the Father. Moreover, the demonstration of love towards the Father cannot at all be fulfilled by the Law's command to love as we love ourselves and with our own qualities.
Unconditional Love brings unity with others and the Father:
NASB, Colossians 3:14 - Beyond all these things put on love, which is the perfect bond of unity.
NASB, John 17:20 - “I do not pray for these alone, but also for those who will believe in Me through their word; 21 that they all may be one, as You, Father, are in Me, and I in You; that they also may be one in Us ...
Jesus affirmed how difficult it was to accept his commandments:
NASB, John 8:37-38 - 37 I know that you are Abraham’s descendants; yet you seek to kill Me, because My word has no place in you. 38 I speak the things which I have seen with My Father; therefore you also do the things which you heard from your father.”
NASB, John 16:12 - “I have many more things to say to you, but you cannot bear them now. 13 But when He, the Spirit of truth, comes, He will guide you into all the truth; for He will not speak on His own initiative, but whatever He hears, He will speak; and He will disclose to you what is to come.
But there isn't a more clearer clarification what "unconditional" means than:
Matthew 10:38 - And he who does not take his cross and follow after Me is not worthy of Me.
It is impossible to claim to have been discipled, let alone claim to be discipling others if one does not know the commandments of Jesus. Christians who make the claim to distinguish the true Love of God from unconditional love towards others are also guilty of the accusation that Jesus made towards the Jews' hypocrisy: "white-washed tombs full of dead mens' bones", (Matthew 23:27),
The Wisdom of God is often Exchanged for the Wisdom of Men:
NKJV, Matthew 28:19-20 - Go therefore and make disciples ... 20 teaching them to observe all things that I have commanded you ...
NASB, John 20:23 If you forgive the sins of any, their sins have been forgiven them; if you retain the sins of any, they have been retained.”
NASB, Matthew 5:42 - Give to him who asks of you, and do not turn away from him who wants to borrow from you.
But, how many times have we heard Christians justifying disobedience to these commandments of Jesus by appealing to their own wisdom - presuming that theirs is greater than Jesus'? "If I forgive and accept this person, they will think that I approve of their actions." And, "If I give this person the money they ask for, they will waste it on drugs and alcohol." Perhaps they are wise in the eyes of the world. Or perhaps they are foolish to pass up an invitation for the presence of God and an opportunity for the Holy Spirit to bring deliverance.
It is entirely consistent, within all of Scripture, that the command to love and bring life - unconditionally - is indistinguishable from embracing the presence of God:
Ezekiel 37:9, NKJV - Also He said to me, “Prophesy to the breath, prophesy, son of man, and say to the breath [the Holy Spirit], ‘Thus says the Lord God: “Come from the four winds, O breath, and breathe on these slain, that they may live.” ’
Disclaimer: Although this commandment is clearly the greatest, it is however the most difficult. I will not pretend that this is remotely possible to observe - alone.