I see! Well, we'd be glad to have you. [ bright smile at each of you!
and now the hesitating part. Hermione looks old enough for combat duty, but Harry and Alma... leeeet's be diplomatic! ]
We have different kinds of positions available. There are the combat positions -- that's where you patrol the dome, break up fights when you see them happening, that sort of thing -- and there are noncombat positions. We're desperately in need of more dispatch people especially, it's a lot of work when it's being divided between only three people.
I don't suppose any of you can heal? [ this he adds with extra hopefulness. they could always use more healers! ]