Well Jehovah's witnesses think it's important to use the personal name of their god, so it's a bit amusing that they get the name wrong. It's like they fell at the first hurdle.

To be fair, the mistranslation predates them. I see they acknowledge the issue and think it doesn't matter.

I guess it's a bit of a coordination/communication issue with other JWs and with the world at large. The fact that they stick with this mistake doesn't mean that individual Witnesses, or the group as a whole, are stupid, or don't understand their own religion.