OP: So, can the Bible's relative chronology be translated into absolute dates?
In a word, no. The converse, however, is possible, and I take it this is what is intended from the way the question proceeds:
OP: What I am looking for are key biblical events that are verified by independent, extra-biblical sources. From such 'anchors', are we able to extrapolate an 'absolute' chronology forwards and backwards, using the Bible's internal (relative) chronology?
This is possible, although I find OP's terms somewhat confusing. From certain anchor points ("absolute" chronology) a "relative" chronology can be constructed/extrapolated, but this remains relative, not absolute.
This more circumspect exercise has been pursued by scholars for a very long time, using certain "external synchronisms" in order to get to grips with the complexities of the internal and relative chronology of the Bible (Hebrew Bible as well as New Testament, although the time scales in the latter make it a much less perilous exercise than for the former).
One excellent example is described by W.G. Lambert (doyen of 20th C. Assyriologists) in his "Mesopotamian Sources and Pre-exilic Israel", in John Day, ed., In Search of Pre-Exilic Israel (T & T Clark, 2004), pp. 355-6. Lambert notes the list of Assyrian officers of state, compiled over many decades, which records from time to time some additional information:
One of these events is a solar eclipse, datable to 763 BCE, which ties down the whole sequence to modern time-reckoning. ... The lists of officers' names ('Eponym Lists') are preserved for the years 910-649 BCE... The years to the fall of Assyria in 612 BCE are precisely known from an abundance of other evidence.
Plotting this kind of evidence against other evidence, biblical and extra-biblical means -- for example -- that Ahab's involvement in the Battle of Qarqar in 853 can be quite precisely chronologically located with a high degree of confidence. Ironically, although this achievement of Ahab's is not recorded in the Bible, it is found in extra-biblical sources, and locates Ahab's reign with some accuracy. And from this point, as OP suggests, the relative chronology of adjacent events can be plotted.
There are vagaries and anomalies, however, so the relative chronology retains some degree of uncertainty. But we are not left helpless.
N.b. This answer should be considered an alpha-release. If it proves helpful, it would be possible to extend it.