I don't see how the bottom barrel could be "bent" since it's so short, or how the new brace could have changed it. If you mean it's twisted so that it's no longer at a right angle to the framing, that makes more sense and would be very simple to straighten out. You could turn that zerk fitting 90 degrees while you're at it so a grease gun tip could get to it.
What goes through the 3 tubes on that frame? I see the very short lower tube in question, the long upper tube, and what looks like just a swingarm pivot at the end.