I think something is missing in this list. I had a recent game in Tibet and both the Timurids, Bengal, and Jaunpur would some times get the modifier. Sure, Bengal/Jaunpur would some times claim 1 province, but they would get WYP modifier for every single one of my provinces. Timurids had permanent CB, but never any claims, as they bordered my capital.
1) 0 cores for either country
2) some times 1 or 2 claims, but it'd still say that they wanted all of my provinces
3) no missions
4) not needed for hindustan
5) very poor land with wrong culture and religion for both nations
6) one of the poorest trade nodes, though it could feed them
I think they just had the modifier because I was incredibly weak ~12k soldiers vs their 80k, 30k, 30k respectively. There could also be many other reasons for this modifier to appear.