Flunra listened to what Calidora said before he was taken aback.
He wasn't expecting her to give him advice.
"If I made the wrong choice, considering his problem with the Lunirich Gods, the end result might be fatal. I'm taking the safer route to consult the situation with him first before making a move myself" He rebutted, conveying his reasoning.
Despite his argument, what Calidora said is not completely wrong.
Rex would really need help against the Executor, he's simply at a complete disadvantage.
Since the Executors are entities that were made to fight against Supernaturals, the fact that he was a Werewolf greatly lowers his chance of winning. He would not only reach their level, but he needs to surpass them completely to win.
A task that is quite impossibly difficult, even for him.
Naturally, he would need as much help as he could get in order to fix his triumph.