Umpire Struck by Batted Ball

With two outs, the runner on second base (R2) is stealing on the pitch. The batter hits a grounder directly towards the shortstop. However, the grounder hits the field umpire who is in the traditional "C" position on the infield grass directly in front of the shortstop. 
 
R2 is safe at third base and the batter is safe at first base. What do the umpires do now?
 
Call
When a batted ball touches an umpire before touching/passing a fielder (other than the pitcher) then the ball is immediately dead (NF 5-1-1f1 and 6-1-5). Runners must return to their base occupied at the time of the pitch and the batter-runner is awarded first base (NF 8-4-2k).
 
In the situation below, R2 must return to second base and the batter remains at first base.