If Ninetails doesn't use solarbeam, ignore this post because I've clearly forgotten what her pokemon do.
I EV trained my Blaziken on Touros, so he has perfect speed and attack EVs (31 attack IV and 24 speed IV as well, I think). That might be how I outsped them with him.
I have horrible recall, and I can't replay the fight (unless someone knows how to with cheat engine or something), but I think what I did was swap Swampert out so something else would eat the Solarbeams. Blaziken then took care of Nintails. Then I swept with earthquake, because whatever came after that didn't OHKO my swampe