Commercial lacto tends to be a bit more potent than lab cultures, so you might be ok. I’ve soured with Jolly Pumpkin dregs at around 25 IBU (then again, they might have pedio). So chances are that it’ll be ok.
The good thing is that hops don’t actually kill lactic acid bacteria, just inhibit their growth. So if you pitch the culture again in low IBU wort, the lacto will start coming back. But then again, you just might create a hop tolerant lacto, which may or may not be a good thing.
3711 won’t leave much left for the lacto and brett, but it should be enough to keep them going. Brett really just needs a carbon source to make an impact, and it’ll find something in there to metabolize. 3711 is a nice choice for a brett saison, though, since it produces glycerol which helps compensate for such a low terminal gravity.
If you find that the culture doesn’t sour enough, pitch it into unhopped wort to promote the growth of the lacto next time.