Is it possible to call the manufacturer? Most keep blueprints on file and are more than willing to help.
From the sounds of it, the nut broke free from it mount. First I would find out how it was mounted, welded, glued... Then since it is damaged you will have to find a replacement. A picture is worth a thousand words. If you could post one and give the name of the manufacturer I am sure someone on here has worked with it before.
VP of Operations / Zymurgist
Bluegrass Brewing Co
636 East Main St