This is a complete strawman
No, it's not. The issue you raise at the end of your scenario is whether if one prays, how does the God to whom one prays know he isn't the second God? If this second God is all knowing with respect to his reality, then anything outside that reality is irrational. You're presuming a metaphysically objective state of being.
No, I’m not. I never claimed God 2 was all knowing.
Yes, you did. I'll quote you.
First, you stipulated:
While definitions of God vary, some of its central [tenets] are that he is all knowing, all powerful and creator of everything.
Then as it pertained particularly to God 2, you stated:
God creates a bubble of reality unconnected to anything else. Within this bubble he creates a being that is all powerful and all knowing with regards to anything inside of this bubble, so this being is free to create anything he wants
So as you see, you did state that God 2 was "all knowing" even if it's with respect to his own "bubble."
In fact the entire point is that an all knowing God is not possible, because even if there is a God prime there is no way for him to know that he is God prime.
Once again, you're presuming metaphyiscal objectivity, which is irrational. There's no knowledge one can ascertain for which one is not the subject. In layman's, your proposition presumes that God can know that which can't be known, which are unknown-unknowns or unknown-can't-be-knowns; and those are irrational. "Everything" falls within the realm of the known, and the "Can't-be-knowns" or "Unknown-unknowns" neither fall within the realm of the known, nor the realm of that which can be rationalized because if they were capable of being known or rationalized they would cease to be unknowns and can't-be-knowns.
Your argument is absurd. You're arguing that there's a possibility--a possibility that is informed by nothing more than metaphysical nonsense--that God is encased within a bubble of which he can know nothing outside. And because of this "possibility" God therefore can't know everything. You haven't substantiated your premise at all, and yet you're extending this conclusion. You self admittedly "imagined" your premise.