Exactly, they were overconfident and they did not adapt their plan. When they could not drop Pogo on the Tourmalet, they should have eased off a bit. And really, I would not have detonated nearly all my team on the Tourmalet given how much racing there still was to do before the final climb. They were in a position to likely have several riders be able to stay with Vingo until the final climb. Instead, they gave Pogs a great draft up until a few kilometers to go. He had to respond to a few attacks, but even if he was a little bit weaker than Vingo, he had much less effort to expend through the majority of the second half of the race.
From a risk analysis point of view, it was a high risk gamble with a fairly good potential to not end up working very well. Perhaps they were overly worried about Jai. It has certainly been shaped into a two rider race now.