Is that a bug? I always thought it was intentional.

I found it slightly challenging to kill them quickly but after a bit they stopped popping up, it's all about effectively killing them.

If this literally is a bug please let me know because I always found this quest hilarious!

Your last step seems to happen if you don't do the quest properly, that's what I had my first run, I think it's a speech check failure?

Have fun!