Quickseller has even backed off and changed his to a neutral. The fact that Quickseller thinks it is appropriate to do so, yet you still resist, is quite telling.
I changed my negative to a neutral because he is no longer offering escrow services. From my viewpoint, the OP probably saw that people are charging for their escrow services and wanted to earn some money in a similar way.
Once he was explained why this is a sign of him being a scammer, he quickly corrected his actions and closed his escrow thread. I think he most likely didn't know the "rules" regarding when it would be appropriate to offer escrow (and yes they are unfortunately unwritten and they do change from time to time based on the community).