>> No, Device B can invite the Device C to join the already running the Group in which device A acting as P2P GO. In P2P Group at a time only 1 device can act as P2P GO. So Device C also acting as p2p client in that group. 1 p2p go with 2 p2p client connection.
the other possibility is that Device C can start new p2p connection with Device B... if user accept the p2p connection request which is coming from device C then first it will terminate the p2p group with Device A & start new p2p connection between device B & Device C.