Where is the proof that he sang them, apart from the Cascio family stating that? If such sessions did in fact occur in the home studio of Eddie Cascio, there would certainly be some proof, be it pictures, videos or even recordings from in-between takes of Michael talking to Eddie, e.t.c.
Neff-U, for example, who worked with Michael during the same period, has shared such recordings.
Additionally, the process of recording described by the Cascio's doesn't correlate with the way Michael usually worked on music his entire life. When creating a demo, Michael would first record a melody, before writing the lyrics, and he would record that melody, occasionally with improvised lyrics over the instrumental e.g. the Billie Jean home demo. But the Cascio songs are fully realised with finished lyrics and ad-libs, allegedly written and recorded over a period of 3 months.
Where are handwritten notes by Michael mentioning these songs? He certainly wrote down songs from this period, which were worked on with other collaborators, on his to-do list in 2009. Why not the Cascio songs?
How come Jason Malachi sounds identical to the voice on the Cascio songs? Why doesn't Michael sound like he does on these demos on WBSS 2008, which was actually recorded in Eddie Cascio's studio, but released when he was still alive.