If you can get the tip of the jaws of an adjustable wrench near the place where the bend is, ideally along most or all of the length of the bend, then you might be able to make some progress. Finding a photo of someone doing this was significantly more difficult than I first expected. Hopefully this will illustrate my suggestion:
The longer the handle of the adjustable wrench, the more leverage you'll have. The wider the jaws of the adjustable wrench, the more uniform your work will be.