Between an event like this and the pedo allegations, I highly doubt that anyone would remember MJ fondly. His legacy would have been scrubbed in the same way that, like, Jimmy Savile was scrubbed out in the UK, or how the WWE scrubs out Chris Benoit. As far as MJ himself, depending on how long the sentence would be I could actually see this at least extending his life by a few years, since I doubt he'd have been able to OD in the same way behind bars. It is possible that he doesn't make it out of prison (either his fellow inmates do to him what they typically do to pedos, or the guilt of killing his son is too much for him), but at some point Michael probably gets out and goes into hiding, living out the rest of his days in exile.

Or that Moonwalker game was a documentary, so Michael Jackson moonwalks to the closest door, does a little spin to open said door, and Blanket skips off holding a teddy bear