Betta Fish: Betta ich or something else?

Trying to figure out what the white dots on his fins are. Treated the tank for ich, the Cory catfish he lives with are healthy, never had any dots. 0 ammonia and nitrites, 5-10 nitrates. I know he fin nips since we got him his fins have grown, the filter flow is as low as can be and he has a floating log and plants to rest on. He seems happy otherwise, makes bubble nests, swims around the same as usual. The Cory catfish are being moved to another tank but want to make sure there is no ich before moving them, so I don’t infect the new tank.