Well, as you describe it, the sniper failed to do his job. He should have taken out the shooter because he knew he was not another SS agent.
Aren’t they supposed to call out “gun!” and implement the special protection protocol immediately when they spot a potential assailant?
This is so odd.
Is it possible the sniper hesitated, thinking the shooter might be local security?
“Who is that guy?”
“Oh, shit!!!”