This is MY opinion:
Let's go back to 1995 to start off. The composer of You Are Not Alone, Robert Kelly, recorded a demo of the track. In the demo, he imitated Michael's vocal stylings (gasps, "hee hee's", etc.) to show Michael what the track would sound like if he recorded it. Keep this in mind.
Fast-forward to when Michael arrives on the Cascio doorstep and stays with them for a few months. At some point, Eddie (an aspiring producer and songwriter) approaches Michael with twelve songs written with James Porte (who was involved as a technical engineer for the Invincible album), in the hopes that Michael would record and release them for his next album. Demos were recorded with Jason Malachi, who was noted as having impersonated Michael in most of his songs and sounded somewhat like him. The reasoning for Malachi's inclusion was to show what the song would sound like if Michael recorded them (a la You Are Not Alone). Michael either agreed to record the tracks at some point or complimented Eddie for the tracks, which led Eddie to making a finished instrumental to present to Michael in the hopes that he would record them during his stay in London.
Then, Michael dies. Eddie is left with twelve tracks that Michael never recorded, with Jason Malachi on lead vocals. Eddie gets wind that the Estate is putting together a new compilation of unreleased music and realizes that he can easily make a quick buck with the twelve Crapio demos. Jason Malachi is contacted and is informed with Eddie's intentions, and agrees. His reasoning is unclear; based on his ego, I believe that Jason agreed to the use of the tracks to see how many people he could fool into thinking he was Michael. Eddie sold the tracks for $5 million (his initial offer was $12 million, $1 million per song) and sat back, hoping that no one would see through his ruse.
Following the release of Breaking News, vocal comparison clips from fans began making their way onto the internet. Celebrities such as Ne-Yo and will.i.am, not to mention Michael's own family and friends, made statements saying that they didn't believe Michael was singing on the tracks. Jason Malachi's own manager, who had heard him record for years, said that he firmly believed that it was Jason on the tracks. Both Eddie, Jason and James realizes that their "clever ruse" was epicly failing. His single TV appearance on the OPRAH show brought forth no new information, other than a few family photos and home videos. When other songs slowly began to make their way online and the fan community was launched into an uproar, Eddie, James and Jason went into hiding. They've all denied various interview requests, and Jason's "third album" that was planned for release in Q3 2011 never materialized.
Also, is there ANY proof that a recording studio existed when Michael lived there?