To be honest, I don't think DonChamp is that great of a play, too many Catcher KOs can be taken, preventing your setup, and even though it has type advantage over ZekEels/EelZone, if they have multiple Zekrom EXs/Magnezones in play, I can see it being very hard to win. If you want something that has a good match-up against ZekEels/EelZone, I would go with either ZekEels with Terrakion or CTM with Terrakion and Shaymin EX. I know it seems like ZekEels would have the advantage over CTM, in theory, CTM almost always outspeeds ZekEels and can destroy Zekroms with Terrakion/Catcher and sweep with Shaymin EX. (I've seen other testing resualts, but I haven't been able to test for myself)
EDIT: Also I know some CTMs are dropping 1-2 Tornadus in favor of Verizion, so it doesn't have to worry as much about the ZekEels player having type advantage over their Tornadus.