Regarding "Strange Riders in these parts", Elturgard was only founded sometime in the first half of 1400s, it didn't exist yet in 1385... So it seems like Moonhaven was around still after 1385..
No, check out the Elturel Forgotten Realms Wiki. It was founded in the mid 1300s, not 1400s.
The Hellriders were around in 1371, so it adds up.
Link to the Elturel Wiki
