SO MANY THANKS to t1cs01 for the original post and to all the people who posted that the solution worked for them: "None of these suggestions worked for me. I was able to extract the files from the QuickBooksPro2019.exe file using 7-Zip, then successfully ran the Setup.exe file from the extracted files."
It worked for me, too!
After getting robot lady and learning that I'd need to call back during business hours, I searched for solutions on the web and voila! You all saved me what could have been many hours on the telephone with incompetent tech support. Sometimes it's good to be a night owl {O O}
