Why ZWJ Insist on Breaking the Du Formation?

One "logical fallacy" I felt watching the latest adapation - why the repeated attempts by ZWJ to "free" Xie Xun?

First of all, this is against XX's wish. XX already declared his intention to stay behind right after the first attempt and show it clearly to ZWJ.

Second, the reason that ZWJ fear for XX safety really doesn't hold.

1) ZWJ knows the Du Monks are enlightned monks with integrity, and they have no intention to harm XX
2) The 3 Du monks promised ZWJ that they would definitely defend XX.
3) ZWJ knows how powerful and capable the Du Monks are

XX is in fact MUCH safer staying under the custody of the Du Monks.

The worst was when ZZR won the tournament and the rights to challenge the Du Monks. ZWJ would know, for sure, ZZR have no chance of breaking the formation.

What did he do? He went to beg ZZR not to harm XX... Wouldn't it be better for him to let ZZR challenge the Du Monks alone and gets destroyed?

Instead, he did the exact opposite by teaming up with ZZR, knowing full well beforehand that it would exhaust himself + the du monks, which again he knew was exactly what Cheng Kun wanted.