Has anyone gone to their first ultrasound and had a heart rate under 100, been told you’re most likely miscarrying, and had the doctor be wrong?

This isn’t happening to me, but my coworker’s daughter. She’s the same amount of weeks as me and my heart is breaking for her and her family. I just want the doctor to be wrong! Has anyone had anything like this happen?

She was told that a week ago yesterday and still no miscarriage.