I ran this idea with my friends and the problems they raised make it impossible.
Reason is, RSS can only control areas where they are in power or where they have a favourable govt to back them up. For ex. MP, Mah, Chattisgargh, Kar etc. In other places they are in direct conflict with xtian missionaries. So , for what you want to work- .ie RSS using missionaries to work, they themselves first need a political environment in their favor. But, such an environment arises only in places where they are already not needed .ie where Hindus have stopped being complete fucktards.
So any question of using Xtian missionaries by RSS/similar org is moot as for Xtian missionaries, conversion of Hindus in places where RSS has no presence is easier and less deadly. This is a problem which Hindus can't outsource