Seeing as they're U/S anyway you have nothing to loose.
If you used heat on them you would need to get the shoulder very hot - bright red, to be able to straighten them up and put a bend back in. Youd have to push the leg up towards the steering tube as you did it to do this.
If you just heat the leg up and bend it open all you will do is put a kink in the shoulder as the tube collapsed.
A lit bit of TLC needed and you MAY get away with it. Definately hot over cold though.
The finish would need sorting after mind. Good luck mate.