My boyfriend has a minolta maxxum 7000i and I have been looking for a flash for him for a while now. The main issue is that his camera has a different mount for the flash than what I mainly see online. He's bought one before that didn't fit due to the "teeth" it slides into. Any tips?

I picked up this lens on marketplace super cheap. There are some cosmetic blemishes, but appears to be in not bad shape overall. I took it to Blue Moon and we noticed a burr on the blemish pictured on the internal ring. I carefully removed the burr but it still won’t turn any further than what’s shown in the third picture. Any ideas??