Yes, it is that hard for me to believe that a kid would ignore his friends and country asking him to join them multiple times - particularly the best player and leader of said team.
But if Draisaitl having a say was even part of the equation, he wouldn't be on the way down now, either. The only difference between Draisaitl's situation now and his situation two weeks ago, is that MacT has taken the NHL AND the World Juniors away from him now, and the Oilers have burned an ELC year in the process.
So he's not developing in the NHL anymore, he's missing out on what everyone else around seems to consider a good building block/development opportunity, and his contract/salary will require dealing with earlier than it needed to. That's 3 negatives to take away from the situation without anything positive for either side to take from it. And MacT is the only one who can (and did) make any of it happen.