>Turns out the drive was so old that Linux could NOT detect the drive.

That's not how things work. If you're using a USB adapter then Linux isn't failing to detect the drive, the adapter is failing to detect the drive. Also I'm pretty sure Linux still supports IDE, not that it matters in this case.

If anything my guess here would be the master/slave/cable select jumper.

Like, last I looked the Linux kernel still had MFM/RLL support, although I'm not sure that's going to get included even as a module in a modern distro.