I did a lot of searching into the people matching Add My Msn's non-proxied IPs:
Wowhamba, RollerBlade Master, Skate All Day, (some other names I don't remember) are all definitely the same person (all sold the same accounts) but for Retarded Nerd I couldn't find any solid matches with the others in the list. I'm almost certain that Add my Msn is none of these people though, because Add my Msn joined while Rollerblade Master was still active, and they both continued being active sythe users until RollerBlade Master was banned 3 months later. Also, in all of these accounts, there are pictures uploaded to photobucket under the name Fatos Kastrati (who is not Add my MSN)
http://www.sythe.org/runescape-2-pictures-videos/960779-some-pics-my-main-account-hawt.html
Example picture, notice the URL:
http://i423.photobucket.com/albums/pp317/fatos_kastrati/98slayer.png
I initially hypothesized that "turn on" is also Add my msn. It was made 6 months before add my msn but it was abandoned after about 2 weeks. The msn for that account was "
[email protected]" and add my msn's name is also "art". But he claims that he never made that account. It doesn't really matter though since turn on quit using sythe long before add my msn joined, even if they were the same person, turn on was never banned and there's 0 interaction between them.
Retarded Nerd was never banned, and has done several bils of trades with r2p recently. In the past, both he and Rollerblade Master were looking to buy a divine though (around the same time period too, but it might just be coincidence)
http://www.sythe.org/runescape-item-purchases/956846-paypal-buying-divine-spirit-shield-trusted.html
http://www.sythe.org/runescape-item-purchases/956547-paypal-buying-divine-spirit-shield-paypal.html
However, Add my msn did vouch him in the past:
http://www.sythe.org/7546047-post4.html and he admits to knowing the guy in real life ("I know what he looks like but I've never talked to him" was what he said on msn)