I'm trying to figure out what the best way to communicate with humans when you don't share the same language. If this was the goal and if I were her, I might do something like this:
1) Webbing them all with the thread manipulation skills so they are immobilized. That'll stop them from attacking and realize that they could die on a whim at that point.
2) Draw something with some medium for them to see. Most likely going to be more thread manipulation as I'm guessing the wall is too hard, and it would be hard for the immobilized to see the ground. So communicating peacefulness and no intent to harm through pictures and judging their expressions to help see what they are thinking.
3) Release one at a time, starting from the weakest, being very careful to make sure they won't be hostile before releasing the next one. If any turn hostile, web them again, and then try again until the point comes across.
Of course if step 1 manages to kill them due to the threads being too strong for them or something, then this plan doesn't work at all.
I'm sure the author considered something like this, and this plan is more boring to convey than just a fight scene....so buh bye Mr. Soldiers. The heroes will probably survive along with any soldiers that give up on attacking her.