Yes, thank you.
He's actually quoting the term used by one of the prisoners to describe the collaborators when he first enters.
Throughout his time in this prison, he plays his cards close to his chest, giving away nothing to his fellow prisoners as he sees they are not useful to the Resistance. However, he does begin to plan an escape with the young Communist when he sees that the youth does have some useful access to the camp power plant.
Anyway, when they come for him,
everyone present knows that it means he is being taken away to his death, and his echoing the earlier insult of the collaborators at this moment when there is nothing to lose is actually the only moment of
solidarity
for those involved. Far from insulting them, he salutes them as fellow Frenchmen as he is being taken to his certain death.

no !!!! you didn't get it !!!!!!
They say "jackasses" ( " des jen foutre " in french) refering to the men who were about to take him away, the french collaborateurs who delivers him to gestapo !
He talks to the guys who are still in the bunk house, but he is talking about the collaborateurs and the germans
Sure it's this way, I ' m fench and saw this movie a little time ago !

I'd say so. He also called them imbeciles earlier in the bunkhouse.