WHOIS Guard Giving a Bad Impact?!

Could this be that WHOIS GUARD is giving a bad impact on SERP?

I did a little learning on Amazon Affiliate sites, picked a sample product (Pioneer AVIC-X930BT) and then researched the affiliate sites that use the model name as their domain. As you can already understand, none of them are mine. All three domain extensions are playing the game: avic-x930bt.com, avic-x930bt.net and avic-x930bt.org. The keyword to optimize is the model number, of course.

So, doing a Google search (avic-x930bt), gives us avic-x930bt.net at the bottom of the first page. This is understandable why he is the winner, since this site has managed to build up 700 backlinks.

The anomaly begins with the other two. avic-x930bt.com has 46 backlinks, and the keyword density 18 2.56%, while avic-x930bt.org has 0 backlinks, and keyword density 12 2.51% Both have the keyword at the beginning of the title tag, both use h1 and h2 with the keyword, and strong tag also.

Now, avic-x930bt.org with his 0 backlinks is on the page 4, avic-x930bt.com, having 46 backlinks, is on the page 6! The only difference there is, is that avic-x930bt.com is using Private WHOIS!