The intention and the manner that China wants to "grab" the institution of the Dalai Lama is a direct reflection of how the Tibetan Government of old and currently the CTA has been using the institution of the Dalai Lama to control Tibetans. The effect is similar to cause, cause is similar to effect.
Only now the table is turned and China has the upper hand. To me all this are worldly activities leveraging of a sacred Lineage, but then the original institution of the Dalai Lama started as a spiritual appointment by the powers of the day during the 3rd Dalai Lama's time and during the 5th Dalai Lama's time it was consolidated with secular powers. Since then spiritual and secular power have rested solely on the Dalai Lama and when the current and 14th Dalai Lama has to flee to India in 1959, he technically lost secular control of Tibet.
My point is, what good would it be for a 15th Dalai Lama do for anyone, given that the institution itself has lost credibility spiritually with the Dorje Shugden ban and secular power is limited to those Tibetans in India with is minority even among the Tibetan diaspora.
The 14th Dalai Lama, perhaps is the wisest in saying that perhaps there will not be any future incarnation and he even in my opinion, "assassinated" the idea of a future incarnation in the recent controversy of his comment about a female Dalai Lama needs to be attractive.
I feel, there need not be any 15th Dalai Lama.