Once we figured it out, we then had to spend half a day going through the Alexa documentation (useless) and random threads on Reddit to figure out how the access control for this feature and Alexa in general works. Like I said, certain changes to your account cannot be made without contacting support and being escalated to a certain team. By the end of it I still could not be certain we had locked this person out because of the number of changes they had made to the account and how much of a mess the app is.
The thing I really don’t understand is that this feature has been deployed for over a year and has received negative attention in the press. It’s just unbelievable that they would ship a feature that can turn your Alexa into a listening device and not think through what could go wrong, and never revisit it in a year.