One of these codes has a problem, it seemed to have deleted all evidence of my rival. This includes: no access to the battle frontier (Flint and the other guy are standing outside), E4 levels are reset, I can't get into the Gym Leader house (Survival area), he is not outside that house, and Crasher Wake is standing in the road on the way to Stark Mountain, but I can't talk to him at all.
I've used these rebattle codes:
Giratina
Dialga (the fixed on)
Palkia (fixed one)
Legendary Birds
Regice
Regirock
Registeel
Regigigas
Darkrai
Uxie + Azelf
Mesprit