In your post I see two different cards. I see a Disk ][ Card and an Apple 5.25 Drive Controller Card.

So basically, this drive can be used in current form on a 5.25 Drive Controller Card and with that dongle it can be used on a Disk ][ Card? (Whereas even with that dongle a Unidisk 5.25 / Apple 5.25 Drive would not work on a Disk][ Card?)

/as you can tell, I'm a mac guy, not a ][ guy, lol )