One quick follow-up - I called Viking re: their letter and they said that due to a "system problem" the date they claim on the letter the car was damaged is actually the date it was "processed" internally. In my case they now are saying the actual rental date was several days before the date they claim it was damaged in their letter to me. They emailed me a copy of the rental agreement - which was absurd since it doesn't indicate that it was damaged upon check-in. Because it wasn't.

Amazing that their hasn't been some sort of class action litigation against this behavior.