Why puzzling?
Those are (or were) thought to be "India-specific terrorists" and if the price for cooperation in Afghanistan is a few more dead in India, would the USG refuse such a deal? I am just curious to know what people think (and what you think)? As always, I have no way of knowing for sure, but from the way things have proceeded in the last 25 years, it seems to me that the USG would be able to live with such terrorism provided it was closely monitored and US citizens were not primary targets and provided there is more cooperation in Afghanistan. Or do you think I am too cynical?