I don't think it's a Finale issue. I did a google, and got this:

https://www.google.com/search?client=firefox-b-1-d&q=emagic+usb+midi+driver.plugin

>I concluded it had to do with Finale.<

Only if Finale is making calls to that driver. All 32 bit apps and processes will pop this message at some point in Mojave — even those that are part of the OS.

It's an information tag only telling you that something may not be compatible with Catalina. It does not affect anything.

Although I am unable to locate the driver on my computer, I since have discovered that Apple bought Emagic in 2002.

It is apparently buried somewhere in the Mac OS. Something in the last OS update must have triggered the popup.

Yes. It's that the driver isn't 64bit.

As I mentioned, even Apple's own libraries are triggering this. There's a USB server that pops this once a week or so on my iMac Pro—again, part of the OS.