You already attached the link to their profile which means you already saw that big red trust feedback warning shouting to their account profile. Coinplay is known scammer here for not honoring the dispute which askgambler already rule out as valid issue agaist them instead they decided to abandon the forum and keep operating without fixing all their pending scam accusation here.
It’s too bad that you knew this forum after you get scammed or else you will avoid them if you are active here.
I don't know if he had seen this profile before he deposited and played at Coinplay or he found it after he have been scammed by the casino. If he has seen this profile before, where there is so much negative feedback, he should not have deposited in that casino.
Maybe there are still platforms, forums where there is their representative and he is active?I wrote a review on Trustpilot.
Anyhow, now the damage has been done, you have been scammed and nothing can be done to recover the amount. Writing the review at Trust Polit may save other people from playing at this casino (if they check the review before playing) but for you, it's a hard lesson learned.