It seems to me that if we need to answer the question of "How" God can be omniscient, then we should also have to answer the question "How" can He be omnipresent.
If I accept because of biblical revelation that God is Holiness, Justice, Love, etc.....then I should also be able to accept with due biblical revelation that God is omnipotent, omniscient, and omnipresent.
God has the ability to be everywhere.
Likewise, God has the ability to know everything.
I don't know that we can answer "How" to any of the questions. We can at best speculate. I agree with you that not understanding how God has certain attributes, or how they work, doesn't prevent me from accepting that He has them as claimed. But my acceptance of those attributes as fact, doesn't mean I have to stop asking questions or speculating.