I am picking up a passenger on United 5334. Please provide a GPS address for the pick up point associated with that flight. The flight is coming into terminal 2 Gate E5

That is near impossible, unless someone was there to do it for you at this time

Really?

Cell lot

Why bother? You already have the terminal (gate is not necessary). Just input ORD and terminal 2 into Google map. You can't miss it (if the passenger has a cellphone, it should be 100% sure). Or, watch the huge road sign and don't be so GPS-dependent.

Park at cell lot

Psrk at cell lot. Ask your guest to call when they've retrieve luggage and ask them to be situated away from the doors of luggage claim area.