I'm not a lawyer and this isn't investment advice so don't sue me if I'm wrong but I'm not sure this qualifies as insider trading in the way that would be illegal for public markets.
Aren't most investors in private companies privy to information that isn't entirely public?
I can see how this feels a bit different because DataBricks might be the size where it might trade with a decent amount of liquidity, but certainly in smaller rounds it's got to be pretty normal.
Maybe if she bought it secondary and the person from whom she purchased the shares was witheld this information they could sue?