Zhou Tian was able to walk out of that gorge alive; it stands to reason that so many deities acting together shouldn't fall in that gorge! Of course, if there really were some trap in that gorge, that situation is not impossible. But now, the benefits that Zhou Tian represents are there, and in the face of greed, it is likely those deities wouldn't care about whether their actions are risky.
Furthermore, even if there is real danger in that gorge, they aren't very far from Zhou Tian. Pursuing and following Zhou Tian's route, those deities don't believe Zhou Tian can use the gorge's strength to deal with them.
Thus, Zhou Tian is confident that his plan can succeed, and at that time, those deities indeed didn't think twice before following Zhou Tian into the gorge.