Thanks for coming back for more support, @GenTent. I appreciate your fir trying all the steps to possibly resolve the issue. 

Condense utility is supported by QuickBooks Desktop 2019. Read through this article to know more about condensing, its limitations, how it is done, and what to do before, during, and after the process: Use the Condense Data utility.

Though, this should be your last option to try to improve performance if you are having performance issues. 

For future reference, you can also check out this article for more troubleshooting steps: Resolve QuickBooks Desktop performance issues: Manage your data file.

We're always delighted to help if you need more assistance. Feel free to post some more.