No need to tell Officer anything. If he sees him getting poked, he'll point and scream "ASSAULT WITH DEADLY WEAPON!1!1" and fire his taser XD. Though if he doesn't see it happen, he'll simply ask you to file a report, after which he will perform an investigation to figure out if it did happen (even if it is blatantly obvious).

As for starting... It's your call, GM. Personally, I think we should wait for another person before starting, but three is enough to begin if you feel like it. I'm wondering where all the people from the Interest Check went though...