This is a brief update...
I resubmitted the entire job, but this time with the
regex_errors box cleared. By default this was in it:
Error rendering document
The system cannot find the path specified
Document not found
I noticed in the "highlights" of the failed frames it was always saying "Document not found"
When I cleared this out, and resubmitted the entire job completed without failed frames. I am testing this further, but would still like some clarification on what is going on exactly...