You even not need a regex for this. You can define a Web Request metric to be used in your BT filter, that uri contains google.com.
On the thresholds, in order to exclude all of them, you should define the lower thresholds (below or equal 0 should do the job)
With that set as filter, those purepaths will no go ahead and you will have all the rest ordered without noise!
Hope this helps
You can add the filter you need to avoid those google.com noise. I usually add not containing filters to static content as css or png.
Those transactions will not be part of your splits on that BT.