The logic behind the disqualification was pretty wonky. The guy clearly said that they are "testing their merit", but then ended up saying something equivalent to "It is your fault that I am murdering you."
How does that make any sense? They wanted to see if someone would function as a splendid soldier, that's willing to act on self-sacrifice to achieve a goal. The MC qualify on all of that, yet he was still disqualified because "but dying means you're a failure". What is self-sacrifice, then?
It was fine up until the guy said that "we're merely testing how strong you are, and you fell, so tough luck" -- which is fine. That makes sense. But don't go around spewing bullshit about "the strong survive, if you fall it means you're a loser" -- when it can very easily mean the opposite. The survivors are the cowards, and those who died tried the hardest to contribute.