Thanks for the template file, sample code and screenshots.
After an initial test, I am able to observed the issue as you mentioned via your screenshots using your sample code and template file. I found that data in some cells (e.g G7, H7, etc.) in the first worksheet are not rendered the same way as per in original MS Excel file in Excel to HTML/image conversion. I have logged a ticket with an id “CELLSJAVA-42784” for your issue. We will look into it soon.
Once we have an update on it, we will let you know here.