In my opinion I think he was below in the caves and tunnels, that connect to all houses and all the town probably. When people heard banging in the floor of the RV, it was probably him below.
Others say because he was infiltrated before like Tillie or the bartender
Seems like they keep getting bigger and bigger every season. How are we going to top Athena in space?
Jim has already seen that lake. Ethan was out that way too. Although I don't think it was explicitly shown that Ethan laid eyes on the lake. But if the settlement lake were the lake of tears why wouldn't Jim just say that?
Clearly she found these pants buried in a suitcase in the forest and shape-shifted into them