I would wait a few weeks and have another scan.
I would tell her to wait a couple weeks and have another ultrasound. Sometimes in early pregnancy, things do not always seem as they "should" be.
I am definitely no expert, but waiting a couple weeks is likely what I would do.. Just to be sure that the pregnancy isn't viable.. It seems like even the Dr. is telling you to wait it out and see what happens! It may be just too early to get a good "read" on anything?! Good luck and keep us posted!