I believe we are all understand the situation and your side of the story quite well, so you can rest assured that we read. The situation here is the casino believe your ID is fake for whatever reason and would be more than willing to prove it to other party, of which I propose you both try to get it re-tried with video verification.

Govt. ID usually have security measures and elements like holograms, QR, UV-light watermark, guilloche lines, and color-shifting surface [amongst other things] to make faking them rather difficult.

Now, as they claimed your ID is fake and photoshopped, you can try to counter it by agreeing to a video verification where those elements above can be validated. Things like holograms and color-shifting elements were rather difficult to prove on a still photo, but can easily be performed and validated through a video call where the ID can be actively shifted to many angles to highlight these elements. Thus, hopefully a video verification can help clarify things and resolve your situation.

About bk8 Vietnam is scam while bk8 Asia is... unknown to you [in regards to its reputation]. It's somewhat rather senseless as I think they are one and same body, they share reputation. I think it's comparable to saying that Shopee Vietnam is scam while Shopee itself is not.