Haha, just found this after you told me about it the other night. I remember that. The shot that killed the zombie was actually a 3rd guy on overwatch.
Having backup and overwatch is key to really making an effort to go engage and find friendlies. You can meet alot of cool people and learn to judge them for yourself, in game, with some mitigation of risk.
The majority of the time I try and make friends the way you did - alone - even with weapon holstered, dressed civilian, etc - I get shot at (and often killed cause I'm kinda exposed standing there talking gun away).
Live every life like it was they day before a character wipe.
