Thanks! I'm amazed at the shortage of information! I had found the TAG article, and the Plymouth Colony records add only a single reference to Mr. Garrett of Scituate being written up for selling wine "without an order".
History of Scituate states he was the first town clerk at Scituate and gives the years 1636-1639, but I guess Anderson didn't find any source to back that up. It should be easy enough to determine if there was a clerk taking records in 1636. Perhaps Anderson believes Richard may not have been the first?
Savage and also McLean (author of the TAG article) assert there is probably no connection with the Charlestown Richard.