If you have any other suggestions I can pass to her, have at it.
"Don't use the money for anything (including, but not limited to, brand new cars) until competent professionals have helped you get a good financial plan in place and you have confirmed that this pile is money is worth what you believe it to be worth, after taxes and such" would be a good place to start.
This whole thing has bad news written all over it. And the more you tell us about them/their situation, the worse it sounds to me.
This is what I was thinking. The more I read, the more I'm like WTF? I can't believe they've already gone out and bought a new car. Though I'm assuming this all happened within the past week or two. I wouldn't do anything until I have confirmation that this is real (i.e. didn't sell it at some point and forgot about it type of thing), sought legal/tax/financial advice, and thought about how to manage it all.
I mean it's awesome that they no longer than financial troubles but that's only if they are careful with how they handle their new found wealth.