No. you're still not getting it.
Violating basic rules that everyone agrees on happens all the time. It's called irregularity, and English is full of it. Irregular plurals are common, and correct, because they have fallen into common usage.
What I'm trying to tell you is there's no formally correct in English. There's no Academy of English that tells people how to speak. What's right is what most people say. Most people say "themselves."
