There's some very interesting stuff in Norman Baker's book "And What Do You Do?" about the RF and in particular Andrew's finances, and some rather more up to date stuff in Tina Brown's "Palace Papers".
Yes, he had to pay Virginia Giuffre $12m (or was it £?) but that was largely financed by a. selling the Swiss chalet and b. Bank of Mum, allegedly. He got £15m for selling the awful "Southyork" house that ER2 gave him as a wedding present. Fergie got very little when they divorced. I'm not clear on whether the £249k pa that the article mentions was in addition to the money he got from the Sovereign Grant or if that was it.
He is in a very awkward position with no real way of making a living, but he is an appalling, entitled boor (at the very least) so my agony on his behalf is, shall we say, livable-with.