People seem upset at the elf, but from what we've seen so far the only logical conclusion is that she might try to look for some infighting in the facility, maybe some other guy wants to take over? If no one like this shows up, it's a good shot that this girl actually did defeat the guy.
But what if she defeated the guy? There will be A LOT of people interested in her, for... various reasons. Maybe vangefull clients wanting to kill her or someone wanting to kidnap her and sell her as a weapon, maybe king or someone will get scared of new Sword Master in the making and decide to throw entire army at her just to neutrilize the threat while they still can.
Really, the dismissal and acting like the children are stupid is the best anyone raiding this hieout could do in that situation, I mean if they care for those children.
And there is obviously the stupid way to do it in the next parts of the story, where the elf is just a MORON, but I will believe author is not THAT stupid.