Duh? He's trying to stay off Peugeot who knows it is 3 wide but cuts across toward Audi anyways. Pretty obvious that the Peugeot driver was being dirty after seeing that move in the chicane. Dumas was just taking it easy, backing off then. He waited and took advantage from Peugeot being slowed down coming off the corner. Dumas saw Peugeot cutting across his nose. Instead of taking them both out, he also tried to move to the left. Even the Porsche tried as well, and it still ended in contact.
Listening to the Peugeot driver now, just look at the smirk on his face. He acted like he didn't even know the Audi was there. Take it as you wish, but it was pretty clear what just happened.