Probably they expected more from kelderman, but it was right to change the plan when they saw there were no domestiques to control the race until the last km.Valter was on the limit precisely because the plan was changed, no one would expect from him to drill the climb all the way to the last km. They wanted to make it hard earlier and then Valter went full gas from the bottom, and lasted as long as he could.
Vingegaard ask for permition way before the climb, Niermann agreed and that's why they rode it like that.
I think vingegaard asked for permition during the climb.