Age old tricks are "age old" because they work at least some of the time. I never have been prone to cutting the head off when there is enough of it left to weld to. Did you use an air impact wrench or impact driver? If the driver failed when you had the critter secure (the outer basket is TOAST). I would take a boxed end wrench and weld it onto that bolt. If that didnt work I would weld a socket over the end wrench, and I have an air impact that would twist the transmission shaft off lol. Just don't use the word can't or beaten where a bolt is concerned. You should always remember that a seized bolt can smell fear, and the bolt likes it.