I'm with your thinking, Coyote. Not likely another cat. I seen cat fight, and they aim to make injuries in head area. Also much scratching injuries as well.
Coyote was in pursuit of an escaping cat and got hold where possible. :idunno :(
I would do this to keep from licking. :thumbsup Does cat have rabies shot current?? That would concern me if bitten by another unknown animal in the wild.
Glad you got your kittie back:hugs
Keep us updated on her progress.