I don't see where BigTimeGaming has claimed that they are investigating the problem. To be fair, the person you spoke to said he would get someone from the team to look at it. And that's it.
Could you pressure Yahoo with the “have you got proof OP got paid” please? I’ve yet to see any “proof” of any of Yahoos claims that Gamdom “paid me the next day”
I don't think pressuring Yahoo will get things moving because he is not part of the Gamdom team. He is a campaign manager who was in charge of their signature campaign on the forum. A campaign that has ended in the meantime. If Gamdom decided to stop caring about their reputation or even scam you, I don't think they would care much about what Yahoo thinks about it either. Additionally, yahoo62278 isn't the one claiming you received your money. He responded to my questions and told me the things that the Gamdom team allegedly told him. So those claims originate from Gamdom and the casino owner.
I am going to get in touch with the Gamdom casino support and see what they say when I send them the link to this scam accusation of yours.