First why do you think MERS is inactive? They are still operating. Second the Mortgage and the Note are seperate documents. MERS was often listed as the nominee for the evtual holder of the Note in the Mortgages. MERS does not assign Notes. They assign mortgages.
The GSE's own the vast majority of Notes, but they have servicers foreclose in the banks name so people do not realize who is foreclosing (lots of former political hacks work at Fannie and Freddie and get paid big bucks for working on the campaigns and staffs of federal politicians so they do not want you to know who is foreclosing while they make their bonuses). Most of those assignments take place pursuant to the mortgage servicing guidelines...NOW, if the note was secured that's another issue.
By the way, properties do not go through bankruptcy, Debtors file bankruptcy. Properties become assets of the estates.
Disclaimer: This answer does not constitute legal advice. I am admitted in the States of New York, New Jersey and Massachusetts only and make no attempt to opine on matters of law that are not relevant to those three States. This advice is based on general principles of law that may or may not relate to your specific situation. Facts and laws change and these possible changes will affect the advice provided here. Consult an attorney in your locale before you act on any of this advice. You should not rely on this advice alone and nothing in these communications creates an attorney client relationship.