Hiding referral link on 7878 method

Hi,
I'm working on the famous 7878 method to funnel reviews on local businesses but I'm quite worried about google or yelp or else finding out that I'm sending traffic from the same pages to the same business page.

Is the solution to hide my referral links?

Are solutions like http://nullrefer.com something that really work ?

Thanks so much for the info!

bump ! Any ideas on this?