Another thought... Are we 100% sure that this leg was raced by 8 teams and not 9? We are assuming it based on 8 stations at watermelons detour, right?
The task with the 8 stations set up was one half of a detour, and for those types of tasks, historically, the set up is in case all teams chose to do the same side of a detour. And with that leg being the fourth leg f the Race, it would fit that the three prior legs were elimination legs.
And as far as I can recall Phil has never gone out onto the Race course to the last team when all other teams has checked in, except for an elimination. Otherwise, Phil and production would just wait for that last team to check in. (That has happened a few times, but I would have to search out when.)