I think I would JB weld it on the back. Or maybe JB weld AND put a slice down the middle of the very end of the pins with a jewelers saw. Then very carefully bend each sliced end over just a little as a fail-safe. It would not have to totally hold the emblem tight. Just keep it from falling off if the JB weld fails.
Just a thought.
With the panel being so thin I'd would not try to peen it over as it comes.
