I highly doubt he got close to 850K.
I did 750k in a rated vstar. it's possible. but my sage teammate did over 1m.
commandos actually have great survivability. there aren't many ppl who can solo me. however, I can't handle two maras. that's waaay too many ints. and honestly, even though one person can't solo me, if I have to kite/kill him, he's done his job cuz i'm not healing anyone but myself.