I understand about the third party investigation but I alluded to AskGamblers or CasinoGuru because if he felt strongly/genuinely about getting scammed and wanted to do something about it, he would have to move his complaint outside the forum and involve people or institutions that would take an interest in his case. If he has to wait until that investigation is complete it should not deter him from compiling his case and get it ready to submit to an arbiter.
You seem to have a good rapport with contacts at various casino/gaming websites therefore it must be a bit disappointing when you do not receive a reply. Having said that, everything points to him having no choice but to wait until the conclusion of the investigation.
I don't think the external arbitration service can bear more fruit for this matter. As explained on this thread [I think Razer also explained to me briefly in PM, which I relayed here], all hands are tied because it's a case of third-party investigation request. Even if we add CG to the equation, best response I can think of off the top of my head is that the arbitrator explained that such investigation can take months, thus they will pause the complaint until there is any further development.
That said, and though writing to Razer is a bit useless now [as proven by several PM that arrived to a blind eye], let me try to take a different approach, to ask for his personal contact [much like other casinos already gave me now] so we can talk seamlessly instead of writing about a case to him. And then we can [hopefully] talk about this and several other cases.