I will make a suggestion, as difficult as it might be for you to agree to it I hope you will accept it. Honestly, I think you should consider locking this thread because you are creating a scam accusation on behalf of someone else when you do not even know the full facts surrounding the case. In the general sense, if someone claims to be a victim of a scam they should create the scam accusation themselves.
When your friend is in a position to create an account here and not only post the accusation himself but also respond the questions related to the case, I am sure community members will engage in debate.
If this situation occurred in August 2023 why did you not make this scam accusation for your friend (if he was unable to do it himself) last year? When you stated they replied via email several times, you did not show screenshots of the content therefore we do not know why they suspended the account and you have not explained what the reason was.
I am speculating but Duelbits suspending the account could be down to having multiple accounts attached to a single IP address or use of VPN or use of service from a restricted area or even exploiting a flaw in a game. What was the actual reason they gave?
I just know this story today, as I said he did not get any reply on email.
In other hand, he only get told to wait on live chat support.