Is there actually one or does this line just refute the modern benoni making anyone who wants to play it play it only as an option against nf3 in the nimzo move order?

8...Nfd7 just barely holds it together, methinks. 8...Nbd7 is busted, I'm afraid, as someone came up with Kd2 after the queen check, instead of the usual g3.

Perfectly playable OTB, maybe slightly dangerous in CC.

Could you show me the critical line where black "barely hangs on with nfd7" :)

Black was smoked here, but allegedly there was an improvement on the 18th move. There are a few other lines, but this is a representative of black's difficulties.

http://www.chessgames.com/perl/chessgame?gid=1053432