Virtual shadowing is worthless and not a substitute for in-person shadowing.
Don’t take my word for it. This question has been posted to SDN multiple times and the med school adcomms posting there are unanimous in their opinion that virtual shadowing lacks any value whatsoever.
The best way to get shadowing is ask at her volunteer site. Doctors who are familiar with her (and her common sense, reliability, discretion w/r/t patient data, etc) are the one most likely to give her permission to shadow. She should mention her desire to shadow to any doctors she interacts with regularly. Also she should mention her shadowing interest to the director of volunteer services at her volunteer site. She can also ask her own primary care physician and ask if they can recommend any of their colleagues who might allow her to shadow.
Networking is critical to getting physician shadowing opportunities.
Another pathway that many pre-meds utilize is working as a medical scribe. That job comes with built-in shadowing.