If anything, the video messages of Kashmiri armed leaders in the past few, either denouncing Pakistan, or requesting help, show that Pakistan is no longer arming them.
The posture of the Army and how the high command has changed following Musharraf also indicates this tone.
The same were also responsible for manufacturing political elections in favor of Nawaz Sharif in 1990. They had much bigger stakes, and did a lot worse even if it won America the war, not even our war, like Imran Khan said, at what cost.
Besides, not the same thing. The Pakistan-Afghanistan border was porous, and Afghanistan was a no man land. Pakistan-India border is not. Only way would be via sea, or Nepal and Bangladesh but I don't think Bangladesh border sports Forests, and is plain, but if cows can be smuggled, so can weapons.