Yep! They really do. Vivio really needs to learn just how stupidly strong Trunks is.

Vivio is going to go on the mission with the Porring monster hunt thing, but Nanoha's there too so it's not exactly, you know, sneaking behind her back. But yes they will show that they are totally capable of handling super dangerous missions by themselves... or get bailed out by someone, if something is actually strong enough to be a problem for Trunks.