Li Yifei still had an impression of Li Xinyue's brother, and that guy was obviously a lazy, greedy slicker who just waited for pies to fall from the sky. Having such a person by his side would definitely not work. He wouldn't be helpful at all and might even bring a lot of negative impact.
In the Flying Hawk Squad, and in his previous mercenary corps experiences, Li Yifei understood very clearly that if he wanted his subordinates to work loyally for him, he couldn't let his family members throw their weight around. For example, if he tolerated a no-good relative giving orders, even if his men temporarily accepted it, they would eventually grow weary of it. Just like in the Flying Hawk Squad, having an unsatisfactory person appointed over him had left troubles behind.