Of course he will let it drop. He will discover that he has no authority to do anything whatsoever with the Knights except exercise control over any religious associated with it and appoint  a prelate to supervise the clergy associated with the order from among three candidates proposed by the Grand Master and appoint or remove an ambassador (patron).

He will discover that the Knights are one the most significant charity medical providers in the world, that the countries it serves will be unsupportive of an attempt to interfere with it, that it is a significant net financial inflow to the Church.

It is rather amusing to see someone normally associated with manning the ramparts against the "Vatican bureaucracy" and various teachings decrying "men claiming catholicity" and advocating for a papal stomping of a lay organization, but I expected nothing less.