All I want to do is distance myself from that POS shop and owner at this point.
That I understand all too well.
I'll try the small wooden blocks sawed to match the lip radius as a die to use with the Vice grips and slowly persuade the lips back into their proper curve.
I've found that the wood "persuaders" conform to the distorted metal fender a lot (yes, it is two words) better than the metal fender conforms to the wood "persuaders". It's called experience.
Find some metal, like small 1/4 or 3/8 id metal pipe, about 1 to 2 inches long for the inner side, and some cutting, grinding and welding on a 3/4 inch pipe "T" to get a solid outer "arc" to press the fender lip into, and then use a large "C" clamp to apply the force. If this seems like overkill, it may work.
Jim