Where was that reported?
Look, this story doesn't even make sense from Pakistan's point of view. Musharraf had already withdrawn support of the Taliban. He had fired his top generals who were sympathetic to them. He had fired the head of Pakistani intelligence for the same reason.
The Pakistanis who were fighting with the Taliban were not government soldiers and advisors. They were Pakistani terrorists who volunteered to go over there.
Even if some Pakistanis from the government were there, something which hasn't been proven at all, they were there on their own initiative. Musharraf isn't an idiot. Now, Hersh and others are saying that Musharraf would have wanted to rescue the very people he was cracking down on at home? It makes no sense.
It does make sense. Sometime politics is played in the margins.
Many eyewitnesses reported air transports landing and taking off from Kunduz. The stories didn't sound like disinformation at the time, and they still don't.