Hmmm, I agree with above posts that the casino shouldn't be liable. A couple of points off the top of my head. First, the 'mental illness' this man suffers from is addiction. These addictive behaviours, although compulsive, are essentially the choice of the individual (i.e., only the individual can choose to attempt to stop). It's a long hard road back but only by acknowledging their own responsibility and really wanting to stop can this occur. Blaming the casino is not the way to get there. It is simply looking to place external blame.
Secondly, I work with those who are mentally unwell and it really gets me when this is paraded around as an excuse. The syndrome they talk about is related to some learning difficulties and possible mental retardation. It ranges from mild to severe. Now, given this man was commiting fraud by getting money for some business project, living independently, and supposedly working, I suspect he is 'high functioning'. In other words, the mental illness becomes yet another external excuse and generally does not impact too much on his day to day functioning and ability to make a decision. At the most it might predispose him to impulse control disorders (e.g., gambling) which he and his support network should have been aware of. It is not up to the casino to be aware of this, and in fact would be impossible (unless they demand medical certificate and histories from all their players).
I don't know what the casino did to 'draw him in' (i.e., the tactics metioned). The only fact as I see it currently in the article is that this man is addicted to gambling. He obtained money fraudulently, gambled, lost and now wants to blame the casino, his 'mental illness, and probably everyone and everything other than stopping and taking responsibility. I fear for this person's recovery when he does not appear to be at a point of acknowledging his own liability in this situation.