If the rest of the roof is still in good shape, why not just patch it with a piece of rubber roofing and dicor. The size of the patch isn't an issue.
I've done several that way. My neighbor hung his as he backed it into his rv port. It had the aluminum radiused edge and damaged about 2' by 10". I straightened the radiused aluminum edge as best I could, coated the area with acrylic cement and placed a rubber patch on it. I coated the edges of the patch with Dicor self-leveling caulk and it's been on there about 5 years with no problems.
As for appearance, most don't notice, it blends in well.