It is not about PKK because that group is Leftist. In India the Leftists don't exactly find a fan base among supporters of the BJP party which forms the majority partner among the parties that comprise the Indian government.
Besides that, the PKK is a Leftist fighting group whose equivalent in India would be the Naxalites who face military action by the Indian paramilitary forces.
Then what's the interest of India in that region? I heard India does maintain extensive intelligence network in that area.