I have a similar issue.  I have a student that I added to my roster, but the assignments that I have given to the class is not showing up for her.  I have checked to make sure that there was a check by her name by the assignment and there.  Is there a way to fix this?

I found a way to fix this by exploring on my own....  I went to the content tab, checked the assignments that were missing for that student and hit the assign button.  In the next screen you can choose who to assign it to.  I assigned it only to the students who needed it.  It gave it to those students.  Only issue is it shows up after the other assignments.  frustrating but at least now those students can do the work.  I just wish I knew why it happened.