In the first phase of Extreme Challenge, everyone seemed to eat in a restaurant, but Yixing didn't like to eat fish. Bo Huang and Huang Lei say that eating fish is good.
The clip you mentioned happened in the third issue of the second season of Extreme Challenge: you said you were going to leave, but the clip of eating was not included in the feature film, but included in the extreme challenge tidbits of the 2065438 issue of I Love Challenge +06050 1. Bo Huang and Huang Lei coaxed the lay man to eat fish, but refused to eat. Finally, they ate shrimp and crab roe. You can find it by searching for "I love challenges" on Youku.