[ORD 2021 R1] Print Organizer doesn't output certain sheets

I used a WorkSet sheet index to create a Print Organizer pset.  All of the desired sheets appear in the sheet index and in the print organizer pset and they preview OK.   Not all of the sheet files get printed to the pdf.  Stranger still, if I open the same pset in MicroStation CE it prints all of the sheets. What's going on?  MicroStation support won't help me because it works in MS.  ORD support hasn't responded in a week or two, so I've gotten nowhere.  Has anyone else experienced this?