Printing Problems with HP PageWide Pro 477

We have an HP PageWide Pro 477 in the office. It has a printing problem:

When you add the printer using its native driver, printing works perfectly.

BUT when you add the printer using AirPrint (Secure or no), when you print, you end up with lots of blank rectangles in place of characters. This happens on all sorts of random documents no matter the font. Even basic stuff using Helvetica.

But if you delete the printer and re-add using the real driver, it will printer normally.

Open and shut case? Well not so fast. Here is the REAL problem:

Where do you get the printer driver? It just showed up on some of my Macs. On others, no sign of it.

When you try to download it from HP, it makes you download a utility that sends you to a web page, which then makes you download ANOTHER utility from the App store, which then adds the printer using AirPrint. Its an absurd process and it doesn't actually get you to the printer's driver!

All Macs in question are on 10.15. I don't know how some of them got the driver. I can only assume it was in a driver bundle that got installed for some other printer, but I have no idea which.

The attached image is for a completely different printer, but it shows you what I'm talking about. If you add it by selecting its name, it works. If you select air print, it does not. But not all Macs have it by name.