Spiritually speaking. Omnipresence: the state of being everywhere at once. Does that mean God is in Hell?

Omnipresent means that He is everywhere. Hell is part of "everywhere." Therefore, God is in Hell. But, Hell does not affect God, and God's grace is not in Hell. God is present in Hell, but His grace is not there. He is not burning. He is just there. He is in Heaven, on Earth, in Hell, and everywhere else in the universe. That's what "omnipresent" means. If God had been everywhere except for Hell, that would not be "omnipresent." Hell is part of God's creation, so Hell is one place where God is.

Omnipresence is a given when it comes to God.

Based on that well known fact why would he suddenly be in hell?

When God separates good from evil forevermore at Judgment, He will be in Heaven He has designed for Himself and all who love Him. Everywhere else is Hell.

Apparently so. Then again, you have to ask yourself if someone really can be omnipresent, omniscient and omnipotent, and still care little enough about humans to "design" such a hostile universe for us to live in.

Actually IT does not exist anywhere outside of your religiously inculcated til believed stories or properly brainwashed children's minds!!! No actual god or devil or heaven or hell exist any where outside of any ones inculcated til believed or simply brainwashed childish minds!!! BELIEFS only need an ear to be "just believed", KNOWLEDGE uses our ears, eyes and brains and all other organs to expand learning into a life of reality, not "JUST A BELIEF"!!!

Being in hell is a choice so God could go there but why would He .. He reserved that place for demons, satan and all those who reject him...

It also means God was in the anuses of every boy raped by a Catholic priest

no...gods and hell are imaginary....so are devils, demons, angels, heaven, holy spirits and sin.....religion is a plague of ignorance on humanity.....