Not sure if the Karankawas (’Kronks’) were maneaters, but I remember stories of the Tonkawa eating defeated Comanche.
I can see why Mexico might want to put Texicans between themselves and some of these tribes, particularly Comanche. They were bad news. (But apparently tasty.)
This page of a book that I have, mentions the meals of Comanche flesh.
Karankawas, I have heard, were indeed man eaters. They’d tie people to stakes and dance around ‘em, cutting bits of their flesh off and eating the chunks while the victim is watching and still alive.