Maybe a lack of a crowd would hurt Ben but Andre wouldn't have a problem with it. Ben went out there to make everyone have fun. Andre went out there to show everyone he wasn't looking for a friend and he didn't need one. Ben likes to feed off the crowd to pump him up Andre is disgusted by people watching him duel. Andre has self control of himself otherwise he'd be a lot more arrogant and vicious with his slander and insults. If you really want to know I'll tell you in a pm why Andre is like that but trust me he doesn't need anyone nor does he want anyone at his side. He respects and thinks of Ben as a companion due to what Ben has done for him in the past. While it might scare Ben to see Shinrei act that way Andre would more than likely just revert back to his, "Oh so we're doing it like that now?" sort of mind set and just grid-lock himself into the duel and ignore Shinrei. It'd probably nothing he hasn't experienced before.