I would stop the vodka dosing. Slowly of course.
I don't know about platehead, but I had it before I had the hair algae and before I started vodka dosing. It came in on some frags and kept growing. My tank is bare bottom no fuge, no sump. My nutrients are high now because I had to rehome a fish for a few months. The vodka works, just not on this algae. It's just nasty. Now it turned into a pinkish white slime/snot that just won't come off. I'm hoping platehead can find a solution that helps me too.
It's not bacteria like cyano. Doesn't siphon. It's hairy/fuzzy, very short cropped, impossible to grab onto. Again, I had mine before the vodka dosing - I am only doing that to temporarily solve a problem caused by rehoming a fish. I don't disagree with the whole TDS, know your tank philosophy, I'm just saying this stuff is hard to get rid of. None of the conventional methods seem to work. I think this algae hitchhikes into the tank and just won't leave.