I’ve asked them why it isn’t listed and until they tell me
Epson, Canon and HP release their print drivers through Apple. At some point, you would get an update through the App Store that says something like
there are new printer drivers available for your Mac... and you can click to download. You may still get this.
That you haven't seen this makes me wonder: Have you an iTunes/App Store account and is your Mac properly registered? You do have the option to skip this step when setting up new and, if you did, that is the cause of your problem.
When adding your printer, it should have automatically checked for the Epson latest drivers if your Mac is registered correctly. If your Mac is properly registered with Apple and you added your printer correctly and let it check for printer updates, the the issue is between Apple and Epson and there's nothing you can do about it.
...except call support and get the latest driver—as you did. The tech you talked to is unlikely to know what I just posted.
Now, try getting a driver out of HP. I dare you. HP will tell you to call Apple and Apple will tell you to call HP and you'll feel like a ping pong ball. That led me to helping Apple fix the print and scan issues that plagued OS 10.6–10.8.1. Print and Scan have worked correctly since 10.8.2. You are all welcome.
Brother does not release print drivers through Apple. Their printers will use the generic AirPrint driver but you need to download the correct drivers from Brother to access the printer's full set of features. You want the Brother drivers.
Canon deletes print drivers from Apple when they consider the unit obsolete. Their Japanese web site is where you can find them for download to see if anything still works. Some of my school clients have these discontinued Canon printers and the Mavericks drivers still work in Mojave if found and reinstalled. There are separate print and scan drivers, BTW.