Everything here! ^^^. Why I had some mixed feelings. Not knowing local laws, neighborhood and local tensions. This could go a few different ways and the employee ending up on a very short stick. I was not abdicating any sympathy to the perps whatsoever.Seems to me a number of things at play here the most important of which is what is the law where it happened, 2nd is the culture where it happened (ie prosecutor willingness and jury).
For example if the law there is deadly force is legal "if a reasonable person would be believe to be in fear for their life" then would the perp jumping over the counter rise to that level? To some it would to others maybe not.
To me if he had been robbed many times in the past by poeple with weapons maybe that would be a factor in whether it was a reasonable response or not (for the very reason you mentioned, if he waited he may have ended up dead).
So to me it seems to be a grey area and that's why we all need to know the laws where we are and also the culture.
Also I think any actions that would be considered "passive/non aggressive/non-escalating" in trying to stop the attack (Fe telling them to stop, get back, moving backwards, etc.) all help in showing it was self defense.
A few things I can see that work in the owner's favor are the perps were the instigator (not the owner), I didn't see any actions by the owner to "prime the pump" in the conflict (ie he didn't "dare" them, escalate, etc), the owner told them several times to stop, just leave, etc. I think all those things will be helpful in showing self defense. But all just IMO...
Another thought is that to us seeing it on video it may appear the perp jumped the counter to steal stuff. But if we were there and we told them several times to stop, leave etc then the guy suddenly jumped over the counter at us we might think he is jumping the counter to attack us.