Why is the offering's progress field BLANK for some learners?

Summary:

We have an issue where learners cannot complete a learning item, we go to investigate and notice that for some unexplained reason, their progress section for the offering is blank and 'not started' vs a 0/1 and 'not started' for example. These learners have nothing to launch. The offering and course are fully reconciled with all changes. What gives?

Content (please ensure you mask any confidential information):

I ran a report of this course and there are over 150 people with a blank progress and a status of not started.

Version (include the version you are using, if applicable):

24A Full Redwood