Unsupported file in submissions causes entire submission to not convert to PDF

If you have a online text + file submission, or multiple file submission, if one of those files does not support conversion (or fails to convert), then none of the documents will show up for PDF markup.

In our case, a faculty member has the student submit a report and a audio file with it. Prior to 3.3, it would show the report, and (obviously) not the audio file. Starting with 3.3, nothing shows up for markup.