I know it has been a while, but do you know what filter in your LMS was being used that could have caused this issue?
I am currently having this exact problem with a course and looking for ideas.
Captivate 2019: 11.5.0.476
Chrome 76.0.3809.87; and IE11
HTML publish only
Self-Paced Learning OFF
Never Send Resume Data OFF
Works in the SCORM cloud.
Have other courses published from same Captivate/pc, loaded to same LMS that are working with no issues, same settings as above.
Tried publishing from different user PC (same Captivate version), same result.
SumTotal LMS 2015.1