Bhai,
Kashmir is not an “accepted international border” like it is between Sindh and Punjab.
Since it is not an accepted border, India could potentially send its own version of the militants back into Pak. But large scale support for India is non-existent in Kashmir.
But the situation in Afghanistan is different. There are many in ex-northern alliance types who hold a grudge against Pak, and thus they can potentially be used against Pak.
However the overall impact is much less compared to the Islamists attack on Pakistan from the tribal areas.
So India for now is happy to take a back seat and watch the “show” in the hope that once Islamist attacks on Pak die down, then India can use the good ole commie lefties among Afghans to start the next round.
As I said, this thread should be restated as: “India to play dirty games in Afghanistan”.