As stated earlier, TDO wouldn't actually be able to control the multiverse. Perhaps a disproportionate amount of power for a god, but the total power he's aiming for is somewhat less than multiversal domination.
Though yes, Serini seems to believe that Xykon's plan is the case. Which really is one of my big disagreements with her. I mean, "TDO gets the Snarl" or "the gods unmake the world but they're safe to make more" are obviously less than ideal, but they're obviously better than multiversal domination.
Xykon hypothetically gaining control of the Snarl himself might arguably be worse.
Edit:
My current headcanon is "Redcloak's too scared to ask more directly" with a good side helping of "TDO's doing the work of an entire pantheon so he's kinda busy".
...What? Most of us are arguing that TDO's side isn't completely wrong. That doesn't mean Redcloak can't be a complete jackass.