That's it?

That's the whole story?

No one was fired? No laws were broken?

I'm not one to give HR the benefit of the doubt, but it is actually quite reasonable for them to find out about something like this and call people in to make sure they're aware of the rules around stuff like "don't represent your personal stance as an official Amazon stance".

And, surprise, if they represent themselves as Amazon, they CAN actually be fired, so it would be perfectly truthful to say "HR said they can be terminated" and also "HR did absolutely nothing illegal"