I don't think Rmcdermott927 is the same person as OgN, although I could be wrong. IIRC, Rmcdermott927 ran some kind of casino at one point, which requires a specific expertise that I don't believe OgN has.
I agree with you. From the evidence I've received, RC uses OG for an escrow for the extra fee without extra protection. In my mind, it is no different than you using a different account to escrow your own deals - you got punished but everyone ignored when OG did it, because he was set up on default trust by Theymos. :/ Of course we do not have OG's side of the issue yet; hopefully he will explain why he was scamming escrow fees.
I don't think I quite understand the specific allegation you are making.
Here you are saying they are the same person. You seem to repeat that claim
here in this thread.
I also don't have any details of any specific transaction. But unless there was a specific promise not fulfilled by RC or OgN, it really is not a scam.