So this looks like an ace in the hole against supa. I'll admit it doesn't look good for him. However one thing we have to keep in mind is that it's supa. That means he does and says things without thinking them through, and he does this as both town and scum we've learned through the months of playing with him.
He could have forgotten the hidden modifier in the office, since the game was 4 months ago. He is probably too stubborn also to admit he fvcked up and forgot so if he is town, makes sense why he would vote for himself instead of be humble and admit he was dumb.
I am not gonna pass him off for that, because it's hypotheticals, but if he flips town, that explains it. I'm all for if it looks, walks, and talks like a duck, treat it like a duck.
The one thing I can't get past is his motivation for trying to town confirm me. This isn't as hard hitting for anyone who isn't me, since only I know I am town 100%. I don't see what his motivation is for trying to town confirm me as scum.