Hi JoeGuestSr,
Thank you for the update.
First, I want to explain that due to the limited resources of our forum, we couldn’t do a screen share with you.
Sorry for the inconvenience.
I tested creating HTML file via File > Save/Save As > HTML again on my side, you can check below picture for the preview of the file in OneDrive, there was no problem. I noticed that you mentioned "I published a workbook, which creates the .html file", may I confirm that whether your steps are same as mine?