“Running away at once would attract attention.”
He wouldn’t have run away. In fact he was instructed to calmly walk away not run away. Once he took the shot he would ducked down below the fence to first focus on putting his gun away and then walk away.
Noone— and mean NO ONE standing on that patch of ground below that fenceline and having a high powered rifle fired over their heads, would not have heard it and known from where it immediately came. The knoll argument is one of the stupidest there is. Going there one can see how close the fence was— and, there is NO way. There were people standing right along up close in the shade from trees there at the fence.