Mick, this is a very unfortunate situation and I absolutely understand your frustration. These are all reps and if you are unhappy or concerned with issues, I think that it is important for you to buy from a trusted dealer with excellent QC or just go gen. If a buyer is honest with his/her sale thread and truly did not notice any "other" issues, perhaps there is a chance that they really did not notice. I can say for myself, that I have bought, sold and traded from day one that I joined RG. I know that my feedback score is low, but there were undocumented sales that all have been excellent.
Some of my past purchases have been great, some sucked, overall I have taken each issue as a grain of salt. I hope that you have success with your issue and have an understanding that they are reps and can be easily fixed.