If you leave default logic in place and do not override anything, just add a socket name VRGripP to the bow and set the rotation on it to whatever feels right. If you only want snap grips possible (no free gripping elsewhere on the bow) then you’ll either want to change the PrimarySlotRange on the object to be higher, or override the GetClosestSocketInRange function and just always return your grip point.
As for setting seated mode, whatever makes the most sense to you and your game.