I didn't experience the exact same thing, but my issue was a bad instrument cluster. I learned that the cluster can lead to a lot of weird symptoms and since that's the first thing that went haywire- might be your problem too. They're not easy to do much about yourself, but it sounds like your dealer wont be a great first opinion.
I got a lot of help from these guys: https://www.instrumentclusterstore.com/repair_or_replace_instrument_cluster.htm and I'd bet if you gave them a call they'd be able to help you figure out if that's your problem or not.