Hello Patty, Thank you for sharing your SL file.
I looked through your file and observed that the quiz slides contain triggers that are disabled and that it states to advance to the next slide when a Q2 variable turns true.
The "jump to next slide when Q2 variable becomes true" trigger is the key reason why you can't submit the interactions. However, I removed that trigger and every other trigger that was disabled in each slide.
Now, I was able to submit all interactions for the course after deleting that particular trigger.
Please review the attached updated SL file and let me know your thoughts.
Thank you!