Something about this seems off. The Guardian is more likely to offer something they didn't think of and is probably offering it right now.At the beginning of the episode, Kovich directly said that Georgiou could go back in time, or back to her home universe. My guess is that the Guardian dude is letting her see that she can't go home again, and then will offer her the ability to go back to the 23rd century again by the conclusion of Part 2, setting up for Section 31.
The Mirror Universe being brought back into closer alignment with the Prime Universe might mean that Georgiou will be able to survive in DSC's new setting. Don't ask me how that works, but it sounds like the realities drifting further and further apart seems to be what's causing Georgiou's condition, so bringing them closer together would solve that. It sounds more sci-fi/fantasy-ish, so that's what I think they'll go with.
Granted, this is what I want to happen because Tyler really rubbed me the wrong way during the second season and I'd prefer not to have him back. Honestly, I'd much rather have Georgiou working with Kovich than Tyler. So would, I suspect, everyone else.