Henry Vaccaro is the one who got control of the storage unit with Jackson items in the first place. I believe Mann is working with him or bought the items from him. TSCM probably knows the connection better.
Everything about the collection has been shrouded in secrecy and confusion. I did exhaustive research and investigation into the subject over the course of several years. In short, Henry Vaccaro owns Vintage Pop (Vintage Associates). He acquired the memorabilia collection and audio tapes years ago--even though the original court order forbade him from taking items belonging to MJ or Janet since they weren't part of the bankruptcy case that Katherine, Joe, and some other siblings were. A misguided ruling years later allowed Vacarro to quickly sweep up everything in there (MJ/Janet items as well) despite the original court order. Howard Mann is a business associate of Vaccaro who has helped with the Web site and marketing etc., they are both doing business under the Vintage Pop name.
They (originally just Henry Vaccaro) had worked on creating JacksonSecretVault and numerous variants of it for many years in order to charge money for online access to photos of these items. In 2004, MJ was successful in shutting down the first incarnation of the site (which was promoted by tabloids, Diane Dimond, etc.) due to the illegalities of the acquired collection which the court agreed with. In 2007, "Vintage Pop" aka Vaccaro made a deal to sell the collection to Richard Altomare of Universal Express, to auction everything off. The parties involved, including Richard Altomare, grossly exaggerated the value of these items (their estimates went as high as $200,000,000) but the auction actually grossed a mere $500,000. Henry V. wanted them to pay him $4 million for the collection but they only paid him $150,000 advance, and as such more litigation ensued and Vintage Pop resumed the alleged rights to the collection. MJ and Janet successfully sued Universal Express/Richard Altomare in 2007 after he circumvented a previously agreed upon settlement and tried to auction off items prohibited by the the agreement. Altomare was ordered to pay their legal fees and turn over the remaining collection he had. In the meanwhile, Vintage Pop and two other companies were also alleging ownership of the collection, but the other companies eventually buckled. Universal Express as a whole crashed and burned soon after the auction mess and is now completely gone--Richard Altomare served time in jail for unrelated fraud after this case concluded, and he never did pay the legal fees for MJ/Janet.
The audio recordings were also part of the Universal Express / Vintage Pop agreement. They had planned on holding multiple auctions, one of which would be for these audio recordings, but this was illegal as they are protected by copyrights. Altomare tried to sell them under the table at one point but was ordered to turn them over to court, although it took a long time for him to do so and he may have only turned over a small number of them to court. Again, they are protected by copyright and cannot be sold. Either way, shortly after all of this mess, Henry Vacarro/Vintage Pop created another site to try and sell the recordings which he still seemed to have access to. He posted terrible remixes of published songs and was seeking millions of dollars for them. However, the tapes were not unique or original as he claimed, but instead were audio tracks for the Jackson Variety Show from the 1970s and perhaps a few other known and released tracks from the Jacksons circa 1970s (e.g., Destiny). At the time, he described them as "unique mechanicals rerecorded for the Jackson Variety Shows which aired in the mid 1970's."
In 2008-2009 (before June 25th) he had another "J5 Secrets" operating where he was charging access for low resolution, watermarked photo scans of Michael and the family that he had acquired from the ill-gotten collection. To deter fans from investing in such a scheme that MJ and courts opposed, I posted higher resolution, unwatermarked versions of all the photos he was charging access for. Fast forward today, and now Katherine and other family members appear to have been suckered into these schemes by "Vintage Pop" aka Henry Vacarro and Howard Mann. Photos from the same collection that I shared long ago and what Vintage Pop tried to charge for have now been converted into the book that Katherine has been promoting through Howard Mann, which they are all trying to profit from...