I still have a problem with this Enyart twist. By definition, an omniscient being knows all that is logically possible to know. To say man and Satan know things that God does not, does not help our cause. The biblical idea of forgiving and forgetting our sins involves not bringing them up again, not divine amnesia (impossible without compromising omniscience...we can remember our sins, but God cannot? Does he know our thoughts? If so, we would remind him of our sins?).
Even Open Theists admit some vs all passages are anthropomorphic or figurative. We should consider Hebraisms, figures of speech, etc. even in the open view. God does change his mind literally (unlike our critics, we do not say this is anthro.), but God having to come down like a man to learn something may not be a wooden literalism. The sun does not rise, but the Bible uses phenomenological language (appearance vs literal). Context does determine literal vs figurative.
The exact nature of omniscience and omnipotence is not clear. I agree that God does not have to dwell on what is happening in hell or a gay bar, but that does not mean he misses a rape and murder that He must judge because He decides He does not want to know about these bad things today. God can handle seeing and knowing all that Satan and man can see and know. He cannot turn off His omniscience, as it were. He knows all past and present knowledge perfectly, the good and the bad. He does not chose to not know the future, per se. He did chose to create contingencies, so the future is inherently unknowable as a certainty. It is not a matter of choosing to not know something he can know, but whether things are a possible object of knowledge. Our past sins are a possible object of knowledge to us, so God does not literally forget them, but chosing to not bring them up again or dwell on them. This is the same for human forgiveness which is not forgetting or amnesia, but a relaxation of claims of justice and pound of flesh. It is letting go of the offense and releasing the offender, not a memory/knowledge issue.
For what its worth, apart from TOL/Ehyart, I have never read a published Open Theist who adds your problematic caveat.