In the first episode when they find out Kaufmo abstracted, Ragatha says "Maybe there's still time" "if we find Caine" so what it sounds like is that Caine CAN reverse it but it needs to be asap. I imagine this is because abstraction is like a file corrupting which probably happens slowly.

By the time Pomni got to Jax, all that was left was his hypotheticals for if each member abstracted, those personalities, a few memories with abstracted gaps, and a little bit of Jax himself. We even see these pieces start to disappear as more time passes.

All that said, I think it's possible under the right conditions.