How to deal with coworker issue?

This is a hospital job doing patient care. We traditionally allow 30 minutes overlap at shift change to divide the workload and get information on the patients we have from the previous shift. This is called "report".

The problem lies with a new coworker who works a new schedule which doesn't correspond to the other shifts. Normally, new shift arrives, report happens, old shift goes home. The new schedule has this person staying 3 1/2 hours into the night shift, then going home. The 30 minutes is still formally built into the schedule, though-it covers a meal break.

We start scheduled treatment rounds at 8pm-the shift officially ends at 9:30pm. We don't punch a clock and it's not a big deal when you leave as long as your work was done and you've given report. The day shift I routinely relieve pushes it, though-if you get to work ten minutes early, they'll be pushing you to take report so they can go (we don't do that to them at all). This new person isn't new to the profession, just to this facility. She's picked up this habit and if no one else has finished treatment rounds by 9, she leaves her treatment cards and pagers and leaves without giving report. Often on ICU patients.

We don't have shift supervisors. I've complained to the manager but now her day shift coworkers are saying I'm bullying her. I don't want to make her hang out waiting but we all carry pagers-I've suggested she page me and come to where I am to give report. This isn't unheard of, BTW.

I know this is long. Opinions or suggestions would be appreciated.