PLI Formatter: This is a rebadge of a third party formatter. It is very similar to a MicroNet formatter in its layout.

AE Drive Drivers: The Mac Driver Museum description is incorrect. The AE drives all used the floppy port to the best of my knowledge.

Onboard ROM: My bet is that it is just stores parameter and declaration data. Many SCSI utils can read it and a couple of formatters have now produced 1.2MB MFM floppies for me.

I think that the paper label is misleading and that the same ROM was used for Mac and NeXT versions of the drive. I really need the software for this one to understand it.