Did that Battle a long time ago so don't know if I Can help, though here are some generic tips:
In double battles You should try to focus on a single opponent, so that You Can get to a 1v1 Battle. In this case, I think You should focus on the minior team, because iirc that's a Shell Smash minior, so you'll want It ko as soon as possible. I know Melia doesn't help though..
Lanturn with boosted defenses May help a lot, and delfox too once You get minior and krookodile out of the way.
You May Also teach lanturn Rain dance ti change field and get an interesting boost vs your First opponents