To avoid danger, Zhou Tian decided to withdraw from the plan. However, under these circumstances, if Zhou Tian encounters danger by withdrawing from the plan, there would be no need for him to continue to withdraw.
Although continuing with the original plan, Zhou Tian is certain that he will encounter substantial danger. Regardless, he believes that there is some credibility in what the Elemental Spirits say. As such, if Zhou Tian makes a final effort, there is a possibility, no matter how slim, of either survival or reaping benefits.
On the other hand, if he withdraws now, the risk is indeed slightly lesser but it's uncertain if he could escape from those Elemental Spirits. Even if Zhou Tian manages to escape alive now, there would not be any significant gains. In this equally dangerous situation, Zhou Tian clearly prefers actions that may yield some gains.