I would suspect this fault occured along time before you recieved the car, evap systems are a sealed system, therefore i suspect that the evap was probly leaking in moisture which collected and turned into water, also vapours are re-introduce into the inlet for re-burn with the in-coming air, but you say it goes into no3 cyclinder, which i find odd !not total convinced as the ecu wont see water, to just shut no3 down indepently
Not saying anything is wrong with the job, maybe just need to understand it better on the description side