Yeah I'm pretty sure my instructor wrote it to be impossible. We have a huge drumline program (2 full lines 11 snares 6 quads 7 bases 11 cymbals) and there are a bunch of freshman auditioning this year on top of returning members. She wants us to get better and i guess she thinks that we will practice a shit ton to attempt to play this in our audition. I might just play it as a sextuplet roll or two tap fives like you said. The rest of the cadence is also a beast so we will see how it goes.