I'd do a deep dive to try and figure out WHY Chrome is converting that badly - are a lot of one placement's visits coming from Chrome, do one of your landers not work in Chrome, etc.
However, if you can't spot any confounding factors, then yeah, kill it. Those stats are pretty convincing, particularly after running them through the usual split-test calculator at http://www.peakconversion.com/2012/0...al-calculator/