Gi-hun could succeed if Jun-ho could find a way in the games. Here are some s3 theories from my side
Jun-ho gets inside the games, and Gi- hun, with all other allies (Hyun-ju, Myung-gi,others) might be an elite team. The Frontman (Hwang In-ho) doesn't know if his younger brother is still alive, after shooting his brother in S1. If he knows that, he might join Gi-hun for his mission, because he can't bear the confrontation and the emotional trauma. I know he still loves Jun-ho, because he donated his kidney to him.