This is that weird one with the message:
"Summerdale has taken control of Mt. Black Nastrond. The region used to belong to Summerdale."
Is it at all possible that he switched the region to Summerdale himself before the takeover was successful, thus keeping the lordship, but due to a bug the takeover continued and then "succeeded". Positive I've seen something like that happen before.
That would have made him a member of Summerdale, right? I'm fairly sure that he never showed up on the member list.