Maya couldn't really fight, or make fireballs, or anything super cool like that. She could track who all was in the infirmary. And slip in unnoticed when the people who could probably sense her activities were in the area. This includes moving past any spidey-senses that might notice some girl being worried about Peter while he's in here resting from his injuries.

...Although after a bit of staring at Peter while he was all banged up, Maya has resorted to scribbling in her songbook while she waits for him to wake up.