Here's an idea: what if they dealt with the 1993 allegations by making a separate short film between Part 1 and Part 2? The short film could be produced solely by Graham King, with no involvement from the estate and Michael's kids. Jaafar is not an heir and he's therefore not bound by the settlement agreement, so they could let Jaafar be in charge of approving the script and making sure the short film is respectful of Michael. They couldn't use any MJ music in it, because that would involve getting rights from the estate, and the estate can't get involved. However, we saw with the "Man In The Mirror" movie that they don't need permission from the estate to use Michael's likeness, because he's a public figure, so there's nothing stopping Graham from making a short film about him and the 1993 allegations without any involvement from the estate. Then they could just release that short film to fill in the blanks before Part 2 of the biopic is released. I wonder if they could perhaps even show the short film in theaters right before Part 2, like the Frozen short film was shown before the Cinderella movie? That's usually handled by studios and distributors (Lionsgate and Universal), so surely they would be able to take that decision without getting the estate involved?
When Part 2 would get to the Dangerous era, they could just vaguely hint at some allegations and show the effect they had on Michael during the Dangerous tour, but without getting into the details of what those allegations are, letting the short film handle that.
At the end of the day, if a simple dentist like Evan Chandler was able to get around the settlement agreement by using his brother Ray, surely all those experienced attorneys working for the estate and Lionsgate can figure out something...