As Both Quinn and Peter exited from the tunnel, Quinn made sure he and Peter both had the mask with them at all times, just in case they were to split up. As for contacting the others, Quinn felt like it was best to do so only when he knew for sure that they were in a safe place and where they were. Only then would he ask for the others to come to his location so they could start to initiate a plan.
The AI system's words alone weren't enough for Quinn to trust. Too many times had the AI hid things from him, and suddenly he had dropped a large bombshell saying that the tenth castle belonged to him. Quinn had long guessed of the probability that the original person the AI system was based on used to be a leader. It was the only thing that made sense as to why he had so much information on everything.