The sudden end to the battle brought the angel squad close to see the results. They were amazed that the brilliant slime had attacked with such strength right away. Especially since the party had already backed it up in previous statements.
It wasn't that they did not believe the strength that the party had. However, they believe that every member of the party would be taking a more forward battle style. Not relying on the strength of a newly formed slime.
This didn't bring the angels' opinion down though. Instead, the caption of their group had another opinion. "You brought the brilliant slime because these slimes are too weak to trouble you and it's the best way to let your new ally grow faster. I understand now. We will strive to share the same mentality in the future once we have repelled the enemies here."