Not an attorney and don't know specifics or Michigan debt & real property law.

My GUESS:  Reads like the specific real property used as security for the "overall" debt has been released.  The financial debt, or at least a portion of it, has not been released.

Seen similar transactions, but never with this funky language.  Borrower substitutes something other of value to secure the initial debt in order to get specific real property released - or there is still a balance on the original Note due, but that balance is now unsecured.  I've only run across these with simple mortgage securing the Note is released text and only knew the backroom details because I was working in the backroom.

Of course, with MERS involved, who knows what it really means.