While I admire the original thinking of the OP, this theory has two big weaknesses:

(A) The Snarl seems to persist very nicely beyond the annihilation of any world containing those contradictions. After a few hundred attempts, surely the gods would figure out how to weaken the Snarl, by empirically finding world building paths of less contradiction.

(B) This idea is philosophically interesting, but dramatically barren. Rich is telling a certain kind of tale. IMHO the Snarl as a real creature helps reinforce the kind of tale I believe Rich is shooting for. So while logically it is probably possible for this tale to conclude with a non-creature Snarl, there is really not advantage here, and quite a few downsides.

The biggest downside: While it is not logically disallowed for Thor to be so confused as to be wildly misleading in his conversation with Durkon, going there would completely suck from the drama point of view. How the heck can anyone clarify any of this to the Readers? If the beliefs of gods are discounted, we need a more reliable authority than the "mere" divine. The Snarl might be such an authority, except as not a creature that path would not be open.

600 strips ago, Rich could have said "oh, let me tack this story to the direction that the Snarl is not even a creature!" At this point, there are too many apparent inconsistencies which are outright insolvable in anything but a very slovenly manner.