<human>: Can you condense the text into three sentences or less?

My less-than-straightarrow brother recently went into a drug deal at some dude's apartment. They asked for the cash and he took out his wallet and gave the cash to them. Then he went to the bathroom and LEFT HIS WALLET AND PHONE ON THE TABLE. He came back and he+the dealers had a few hits/lines/bumps/pills of whatever it was he bought (he didn't tell me what he bought from these guys); so I'm assuming it was a fairly laid back atmosphere.  
  
They didn't take anything from his wallet. But of course his wallet had his ID, credit cards, etc. So now they have all the evidence they need to blackmail/incriminate him if they wanted to.  
  
Nothing's happened to him yet. But he's extremely worried that they'll eventually find a way to reach him and extort him (ruin his life, future, and so on). Besides this vice of his, he's a regular college student.  
  
Two questions: 1. would you be worried? 2. what do you think my little bro should do? Seriously, I feel like kids in their late teens/early 20's act so tough, but seeing him like this reminds me that he's still the same kid brother I've known for two decades.
<bot>: Brother idiotically left his wallet on the table at a drug deal and stepped away for a minute. Nothing was taken and nothing has happened yet, but he's really worried that he'll get blackmailed or something. Looking for helpful advice