"I think you read it wrong.
It clearly follows this route in the email:
1. Stuart borrow money from Josh.
2. Stuart apparently ask GAW to pay Josh the money that Stuart borrowed from Josh.
3. Josh says Stuart will then pay the money back to GAW that GAW paid to Josh for the money Stuart still owes Josh.
Its a clusterfuck, and makes absolutely no sense."
Why not read it this way: Josh *says* that Stuart Fraser borrowed money from him, and Josh asks GAW to pay him $150k, and also says that Stuart Fraser will pay GAW back. Given Josh's tenuous relationship to the truth, why not assume that this might just be a cover story for embezzlement?