As a former IT'er, I can only say: That's your code as FBI? Seriously? You deserve those dead members, considering the flimsy, basic code you dared to use. Impossible to crack my ass. That's straight-up kiddy stuff you're using, the type we had to solve when going to summer camp. You started with the codes that only need to be mirrored, and at the end of the camp you solved these kinds.
Honestly, they might need some decent advice from the NSA. It exists specifically for that reason.