Billy, heres the steps I followed to get to the issue...
Filter list by missing fanart (I can see perhaps 30 movies listed)
Select Batch rescraper wizard
Choose Attempt to download fanart for Movies
The process began...(I did notice that the screen seemed to refresh at each fanart request)
My list continued to get shorter & shorter until there was none left.
I check some movies & they still do not have fanart, but the missing fanart filter now reports 0 movies.
Rebuilding the Movies did fix the issue though.