That's actually the way most of them are. You HAVE to use a heat gun and gently and patiently stretch it to fit it on there. Ppl have successfully done it. And then some rush and aren't careful and end up cracking it.
I didn't have this problem with my bumper. The lip was actually too long, and there was a significant overhang on the cornet of the bumper, that I filled up with a stack of washers when i was screwing the lip to the bumper.