Hi @Mark_Ortmann,
Thanks for the reminder to check out the new Excel Writer on 4.3.1.
I just tested it and confirm that this problem is fixed! Thanks again!!
With 4.3.1 though, it seems like there is another issue with Excel: Sharepoint Online Connector + Excel Reader sporadically would fail with error message: Execute failed: com.microsoft.graph.core.ClientException: Error during http request. I created a topic for this.