Only if that target is found by another NPC who’s not also a target, and if they are a target, only if they notify someone before you kill them.
Not really a mechanic but I really hate those proxy triggered conversations in which you HAVE to stay and listen to the entire conversation in order for something to happen. For example, the three woman talking about Kronstadt in Mendoza.
In order for them to leave / change their route, you must listen to their entire exchange between them, you can’t trigger it and leave because for some reason they don’t continue talking unless your nearby, and you can’t bump into them to skip the dialogue as they just return to where they left off, you just HAVE to listen to it.
Same with Aron Ford Jr or whatever the fuck his name is, if you don’t trigger the intel collected thingy signifying that his phone call has ended, he RESTARTS the ENTIRE PHONECALL with yates AGAIN.