The right to be forgotten is an individual right, not a public entity one.
OP, what you have to do is find all the keywords that bring in this serp result, pick the ones you want to push back, and build multiple web properties so that when a search is made, the bad listing is either lost or driven off the front page. This is why repman is so expensive, you may need to rank 40 or 50 sites to clean up three keywords.
Are the complaints valid? If not send a letter to Google and scamalert asking for the page to be removed because of defamation. This is the old way to remove these things, and it sometimes works.
Needless to say, more positive reviews will make the few neg ones look like they are from people who you just can't make happy.
For this you need to actively seek out good reviews. Here is a simple system that was shared here that you can use as a guide to build your review portal from.
Code:
http://www.apexoffers.com/repman/
Create a QR code for this page, and ask customers to scan the qr code and leave a review, especially when they are very happy with your work. I can set this up for you if you need it.
If the complaints are legitimate either resolve them through the site resolution process, or start building web properties.
If the complaints are legitimate, you also need to fix the problem that cuased these unsatisfied customers. There is no sense cleaning up everything and destroying it all over again with shoddy work.