Glad you got it off! I had a similar situation not long ago where I had to get some ancient pedals off in a time window with bike shops all closed. I tried all the standard tricks and then started to make stuff up in desperation. The way I got them off was with a standard 15mm wrench and a hand sledgehammer. A couple pounds on the wrench end and it was free. The heat / oil probably helped as well. I heard hammering is a bad idea but it worked for me. Sledgehammers have a lot of mass so put a lot more inertia into it compared to a regular hammer.