Everything you posted is essentially true except for a few minor details of note.
There are 3 categories of Retained Assets...(1) Trading Assets, (2) Available For Sale Securities and (3) Held To Maturity Securities.
We know for a fact WAMU owned (1) TA's and (2) AFSS's...NOT (3) HTMS's.
We also know that JPM acquired these assets from the sale of WMB, based on their filings since 2008.
What is unknown however is what INTEREST(S), if any, did WMI retain in those assets now held by JPM.
Prior to the bankruptcy, either all or part of the returns from those assets were pledged to WMI, as WMB's sole parent.
This is not up for debate since such distributions from subsidiaries to WMI are documented in multiple sources (Prospectus's etc).
What needs to be determined is whether these "intercompany agreements" ever existed and are still valid.
This needs to be determined, not continuous rehashing of already known facts to score MB points and accolades from the gullible.
To date I have seen nothing that supports the above, this leads me to believe that any such assets/interests are now long gone.