Do you mean that the French Army mutinies again?
I think it's certainly possible if the stalemate drags on.
Petain had retrieved the situation - for the moment - by stopping any big offensives until the Americans were on hand to provide numerical superiority. But that can't continue forever. With the Germans holding a sizeable chunk of France plus almost all Belgium, the offensive has to be resumed at some point. It's a question of when, not if. And if the new offensives bear no more fruit than the old ones, it may not take long for Petain's good work to be undone.
However, it doesn't absolutely have to be a repeat of the Nivelle mutinies. The German armies didn't
mutiny, in the usual sense, during the Hundred Days, but their morale crumbled to the point where they were allowing themselves to be taken prisoner in vastly larger numbers than they ever had before, with more captured in the last four months of the war than in the previous four
years. If they could see no light at the end of the tunnel, this could equally well happen to French troops and even (whisper it) British ones.