In the case of the three older teen shooting...MAY have done the same thing. Although it sounds like a very lame & suspicious reason to use a phone ??? Someone that has intent to immediately shoot you will most likely do so. Everyone has cell phones and men do not usually stop for directions,,, especially coming to someone's door!! Huge Red Flag!!
Its easy to 2nd guess woulda-coulda-shoulda.
I can remember when hitch hiking was common and not fearful for either party.
Back to OP, I would have most likely came out another door with gun & light in hand to observe without being seen first.