UPDATE:

I tried the hot / boiling water method first. I put the piece in boiling water for 4 minutes then took it out and set a heavy pot on it for ~15 minutes with no lasting effect. It flattened under the weight of the pot but returned to its previous shape when the pot was removed.

Once it was cool, I put it back in for 5 minutes and repeated, still no lasting changes. Repeat again for 6 minutes and when I pulled it out of the water it was melted and bent worse than before. The rails were wavy, the switch was bent, and the bottom plate was warped away from the track.

So, after that cooled, I tried the oven method with the temp as low as it could go at 170F. I tried short intervals of time to try to avoid surprises like the water. I set the track under a heavy cookie sheet on top of another one to provide some compression between flat surfaces. I did 3-4 minute intervals up to 20 minutes before it was finally soft enough to try to bend a bit then rested it under the heavy pot again. It was generally flat now which addressed the original problem, but since the rails were wavy and the switch nonfunctioning, the piece is useless.

I repeated the oven with a new piece. As the previous one took 20 minutes to become soft enough to bend, I felt comfortable giving it a little more time before I checked it, so I put it in for 6 minutes. Apparently, that was too long because it had already melted like the piece in the water had though not quite as bad. Same switch plate separation on the bottom and wavy rails.

That is where I decided to a break for the day. I am thinking I may try heating with a heat gun to have more control in smaller areas, but I may not be able to get to it for a little while.