You're probably referring to the idea in the OP. The idea in the OP is not actually what you'd usually read about if you read a typical article about the speculative theories about 'multiverse' -- instead that idea in the OP is actually an certain idea called the "Many Worlds Interpretation" of Quantum Mechanics, and is not widely subscribed to among physicists. It's a peculiar type of multiverse theory in effect that is a very different class of thing, sorta like how a car is not like a herd of horses.
Regarding the typical multiverse speculative theories -- they are largely irrelevant to ordinary life in every way: even most physicists think we'd never be able to know if they exist even if they do. You needn't worry about (typical) multiverse theories having any implication about God. He is the Creator, meaning really that He created all that is, even things we do not know about.
God has done things we do not know about even in this Universe -- we know this because we constantly find new and surprising things in nature and the Universe.
He is the Creator. This means He knows far more than we do. We cannot then categorically assert He could not have created multiverses (along the way), as if we have that omniscience, see.
But, yes, as I see it the idea in the OP is a mental speculation that has nothing to do with our actual reality. It was already that way in trying to reimagine God as different than revealed. That's the more fundamental reason it's not relevant to ordinary life, because it already was saying: imagine God to be totally unlike how God is as we have learned.