heating it will do nothing but make the resin brittle and crack. They only way it could get warped is if the part was pulled prematurely and just let sit to sag with out curing the part. Even if it was pulled the next day after it was laid up, it still takes a few days for it to fully cure.
Anyways, solution to fix the problem.
1-get the supplier to replace the part (which is unlikely)
2-cut and stitch the part back to the correct place
3-place on a table, clamp one side down, twist the part to the correct shape you want it to be. clamp that down and glass in ribs supports, can be made of fiberglass, cardboard, clay, wood, metal, whatever you want to use it all becomes rock hard after you glass it. This will retain the shape after it cures.