This actually is similar to what a co-worker did years ago. But instead of creating “Murray”, he blamed himself. When customers complained “Why are you always out of the ad items here?”, instead of making excuses he just said “I’m sorry. I screwed up. I didn’t order enough. I’m such an idiot.” Next thing you know the customer is saying “Oh, no, it’s OK” and apologizing to HIM. Worked every time.
This tactic, however, is awesome. I am instituting the Murray Principle at my store immediately.
You might want to find some name that can be male or female like “Chris” or “pat,” although you surely would want something less likely to be an actual employee.
Or, for that matter, “Jody.”