Even in the lawless underworld, one needs a reason to kill!
Such a reason is nothing more than an excuse.
Lei Xiaotian wanted to seize power and eliminate Chen Yao but since Chen Yao was above him, no matter how many excuses he could fabricate, he could not publicly murder Chen Yao.
To eliminate Chen Yao, Lei Xiaotian could only use the hands of others. So he thought of Li Huai and Xie Bing. There was no deep hatred between Li Huai and Chen Yao, but Xie Bing did harbor such resentment. It was in line with Xie Bing's character to want to kill Chen Yao, and even if people suspected collusion between Lei Xiaotian and Xie Bing, so what? Would Xie Bing not want to kill Chen Yao without him?
This was why Lei Xiaotian didn't oppose Li Huai and Xie Bing before, even when they were creating trouble in his territory. Instead, he pacified them.