For Jacko, I think it's just about the money. I think the more interesting question is what the Saudi's see in Jacko?
Even they must see he's a has-been and his track record on business ventures is not great.
Maybe they saw an opporunity to use him as a frontman to charities (children's?) which they control. Could be a way to funnel cash.
Jacko get money and kids; so he's happy. The Saudis have a new way to support their terrorist buddies. Looks like a win-win for them.
Jacko's buddy Prince Alwaleed bin Talal has donated to the mujahideen. He also gave $6 million to Palestinians thrown out of work by the intifada, and he helped reconstruct Lebanese power plants destroyed by the Israeli air force (source).
[Removing tinfoil hat]