To have other property covered by that mortgage, the legal description must show all the properties (otherwise they cannot foreclose on any property except what's on the mortgage).

We don't use lawyers in Michigan for title.  You CAN if you want, but it's usually done by Title Companies.

Your closing sentences are coming to the same points and conclusions that just about everyone else has!   Bottom line:  SOMETHING STINKS.  Fortunately, I've had nothing to do with any part of this transaction, but for reasons of my own, I'm going to make sure the county treasurer and assessors hear about it.