G'raha being an all rounder is a story point that is mentioned in side dialogue, so I really doubt he's suddenly gonna forget how to cure or tank.

Quote Originally Posted by Rosenstrauch View Post
By the end of 5.3, the WoL possesses a magic stone with the power to Call heroes from beyond the rift to aid them. There is really no reason we couldn't use it to summon Ryne to our side if we turn out to need her help.
This is a good point, too, in addition to the fact that Ryne not being canonically present wouldn't actually change how the Trust system works.