Having a UI that gives the customer no audio confirmation that it got a command to record and send a message is a serious UI failure. This isn't a small thing here. If a bug like this makes it though, how can I trust that device.

I don't think the article is indicating what you say. The report says it's a bug, but it does bother me why Amazon won't comment on the specifics. This should be patched immediately with a full retrospective explaining what happened.