LOL, look at that brush, do you really think she was up to 30 yards away, and yes, you should be able to tell if the cat is a well kept pet, or a feral cat, especially when identifying your target of a neighborhood cat, before you kill it.
This is one of those examples of the pet already having been killed, so the mistake is obvious, the shooter didn’t know what she was shooting, or she did.
Another point would be that “chipping” of cats is common today. Catching the cat alive and running a scan on it would be the only sure way to determine that nobody has a claim to it.
So thick brush is your excuse for why she should have been able to know it wasn’t a pet cat?