Like you, I believe that Google's workaround still infringes on Lang's patent. But the only one person that ultimately will decide this issue is JJ, and if JJ sense a Google's deceptive behavior that wastes the court time and resource, then JJ has a good reason to rule a RR to the tune of 5% or 7%.
Vringo's strategy in the workaround:
1. Convince JJ that w/a still infringes on Lang's patent, AND
2. Expose Google's delay tactic. To do this, Vringo needs Google internal emails, dispositions from Google's employees, and all other documents.