Question about Sony Disc drive for PS5 Slim Digital Edition consoles

Runs flawlessly in the PS5 Pro. Unpack, plug in, done.

Unfortunately I can't answer that because I only have the Pro.
At least the packaging says that it is compatible with the Slim & Pro.
Hope I could help

It works with the Pro and the Slim, but not with the very old, large digital version

Yes, it is the same drive as if you were buying a slim with just this drive!