Lenny can be found in the Yucatan Casino at the same time as Ted, he will barricade himself in the manager's office. The only way to get him to join is to deal with Snowflake either killing her or taming her. When he joins he will show Chuck how to turn on all the slot machines in the casino.
"If you'd been there what would you have done differently?"
This article is non-canon and not considered part of the official Dead Rising story.
Just like in Dead Rising 2, Lenny will be in the Safe House cafeteria during the unmarked mission 'The Secret of Charlie's Gold'. However, he will give Frank a keycard that grants access to the Fortune City Bank as well as the Yucatan and various other casinos.
Lenny's stilted speech pattern, constant references to his wealthy brother named Charlie, his notebook description and ability to help Chuck gain a lot of money from the casino are a reference to the film Rain Man.
His last name is pun on "Money", which refers to his skill in hacking the slot machines.