Here's the really suspicious part:

Why is the dude bringing $900k in a paper bag to buy a house in Phoenix?

You don't buy a house with $900k in cash unless you're a drug dealer -- and even then you don't, because that's not a good way to launder money. The seller wouldn't accept that type of cash without issuing a Currency Transaction Report (CTR). Laundering works by making the original cash "hidden" to where you can claim to have turned a small amount of money into a large amount of legitimate money, when in reality you're just cycling a large amount of cash through, taking a likely loss, and coming out with still a large amount of legit money on the other end. This is why casinos and poker rooms are so popular for laundering money.

Anyway, if the money was legitimately obtained, he would simply wire it to an escrow company to purchase the house. If the money wasn't legitimate, he wouldn't be carrying it to buy a house in cash.

There's something weird about this whole story. I even wonder if perhaps the guy chunked off the money in a different casino, and bought a $100 hooker so he could pin it on her, so he has an excuse to tell his wife, boss, whatever.