what is likely to have happened is the user who was hacked used the same password as their email address, which without them knowing was likely compromised. whoever got into their emails probably saw the poker chip forum emails about buying and selling, did a quick scan of the site to familiarise themselves with how the forum works and took the opportunity to scam. happens a lot on other forums. change passwords every 2-3 years to avoid this happening to you, and enable 2fac as advised by admins.