Yes I can't really blame India for allowing the Dalai lama in, he was a refugee after all, it had nothing to do with sovereignty over Tibet.
India's core interests involve the protection of various minority groups, including refugees. They couldn't have turned him away.
Very valid point you make up there.
The Chinese can find fault at some of Nehru's actions. But sheltering the Tibetans refugees definitely should not be one.
It would be have been impossible for Nehru (or any other Indian PM for that matter) to not give shelter to the inflowing Tibetans!