I am wondering is there is any other purpose for the 2 slots on the sides of the Z plate other than for attaching the dust boot?
If you have earlier than Gen2, then yes that’s the only ‘designed’ purpose I’ve seen for them, though many dust boot designs don’t use that mount point now. I’m sure folks have used them for other things.
IIRC, though it’s hard to tell from the pictures, those slots have been removed on Gen2 machines to make the Z carriage narrower, which was one of the ways 1F managed to get a bit more usable width in the X axis.