Seeing as there have been new Great Beasts introduced since Byrne I'm sure there can be some kind of retcon to bring both origins in line.

I like the curse spreading as it's been pretty much the same for decades so needs a bit of a twist; it just takes some fine-tuning to make everything fit nicely.
To what extent was the Chaos King involved in the Hulk ones? Was there a reason for the curse's manipulation?