https://carm.org/open-theist-whether-or-not-god-can-make-mistake
Matt Slick is concerned with philosophy/semantics, anything except the Bible (as shown before). In one conversation, Slick wanted to make mistake mean something other than what his opponent would have it mean. Slick just interested in semantics. Here is the dialogue, interestingly quoted with pride by Slick on his own website. It is apparent that Slick just doesn’t understand what he is talking about:
Matt: You said above it would be a mistake, right?
Stan: You said it.
Matt: I thought you did, my mistake. Okay, now if God expects something to happen and it doesn’t, did God make a mistake in his judgment? …in his expectation?
Stan: No. He expected it. It didn’t happen. The question should then be why? Why didn’t it happen?
Matt: So if I expect one thing to happen and I am wrong about it, then I didn’t make a mistake in my expectations?????
Stan: If I were an omnipotent God and expected something to happen, but it didn’t, if I refrained using my power to make it happen, it would have been a mistake to expect something to happen. Do you agree?
Matt: That isn’t the issue.
Stan: But that is the issue
Matt: I said, if God expects something to happen and it doesn’t, did God make a mistake in his judgment?
Stan: Its about God’s power and ability to make the future happen in accordance with his will.
Matt: Let’s ask it again: If God expects something to happen and it doesn’t, did God make a mistake in his judgment?
Stan: No Matt, he did not make a mistake. If you expect something to happen, but it doesn’t, there could lots of reasons from point a to b as to why it didn’t. After all, you never expected to become a Christian. Yet you did.
Matt: So, when you expect one thing to happen and when you are wrong about that, that is NOT a mistake??? correct?
Stan: It wasn’t a mistake at the time.
Also see Slick Mocks God.
God is Open 
Yes, Slick will hammer upon this type of thing, thinking and thinking of a manner to word it to provoke the answer he so desperately wants to be said, disregarding all explanation. And he claims that others do not understand Calvinism, when his desire to twist the owrds of others to say what they do not hold, say or teach shows HIS misunderstanding or an evil desire to misrepresent things.
“Give my answeeeeeer!!!” (rages/cries) = Matt slick = a naughty child disobediently stating: “Give me a coooiiiieeeee!!!” (rages/cries). :-D
“it would have been a mistake to expect something to happen. Do you agree?” I wouldn’t agree with Stan’s idea there but I believe that from the end of the excerpt, Matt doesn’t understand presentism.