"with operator access via messenger" means that you need to click on my profile link on this site, then '...' sign of actions and choose there "Messenger" link. On a new page just write me the operator access of UNA (in the case when your UNA site is available). It would help to understand your second problem with non-English languages, I can't reproduce similar issue.
Hello Michelle, you sort of have this list. On your site, go to EN, you will see the missing keys like this. This is why you can not find them if you are positioned on the language that has missing keys.
In this example, two keys are missing in my FR language.