Ok, this is the first time I've recorded a response, but I'm getting sick of typing the same thing out over and over again, and it seems to be hindering communication. Basically, my point is that if we're in an indeterministic world, then God can't change people's free choices and them remain free, and if He isn't changing people's choices, then they have alternative possibilities, just as the PAP requires.
Kane writes, "if free choices are undetermined, as incompatibilists require, a Frankfurt controller like Black [or God in this case] cannot control them without actually intervening and making the agent choose as the controller wants. If the controller stays out of it, the agent will be responsible but will also have had alternative possibilities because the choice was undetermined. If the controller does intervene, by contrast, the agent will not have alternative possibilities but will also not be responsible (the controller will be)" (Robert Kane. A Contemporary Introduction to Free Will. New York: Oxford, 2005. 88.)
So, omniscience is really irrelevant to whether this works or not.