Even if it's not as necessary now, Trunks is still on alert while she's recovering. It's prudent, and they don't need either of them getting hit with arrows either or ambushed or something. "I'm not sure I'd want to have a trap without us being able to counter the arrows."

Too many ways that could go wrong for them, since they wouldn't be able to properly control or counter the arrows.

"Any chance you're able to modify or erase memories, or put people easily to sleep or something?" Which for this group, Trunks really wasn't worried about anymore. Even near the end, where he'd been moving faster than all but an expert-athlete, things had been so chaotic it hadn't been too hard to disguise it. IF Nita could though, that might make things easier.