Trump didn't incite the violence but he has had lots of opportunities to stem it while freestyling and does crap like this.
The only time he condemns the behavior is when some staffer writes the script and he unenthusiasticlly reads it off a teleprompter.
If he's not inciting violence, then people (if they're being honest, which most political commentators are not) need to stop talking as though he is. Should he joke around when some redneck jokes about shooting people? No, but it doesn't promote violence anymore than Obama's comment about bringing a gun to a knife fight (which some Republicans criticized) promoted violence. Were both comments ill-advised? Yes. Promoting of violence? No.
And if he had shut that guy down by saying something like, "no, we don't shoot people. We just enforce the laws," it wouldn't have stemmed violence. (Frankly, it probably wouldn't have gotten any meaningful news coverage.) The El Paso shooter still would have gone on his rampage, because he's a nut. I don't mean legally insane. He knew what he was doing and knew it was wrong. He's a nut because he has nutty values and beliefs and was willing to do something nutty to enforce those values and beliefs.