I think the issue was by ths following , Patrick's answer pointed me in the right direction. The solution was to move the entire package folder into another folder and then run the "godoc -http :6060" command again which forced the update. For just creating a godoc, this works fine. You just can't actually build anything without changing imports or moving the folder back.
How can I jump to the documentation of the type of a field in a struct or a method I'm browsing in godoc?
Hope this helps The issue isn't modules so much as GOPATH. There's a github issue thread that discusses this in more detail: https://github.com/golang/go/issues/26827 That thread has evolved a workaround that uses a docker container to run a godoc server with GOPATH set to the base of your dev tree. That godoc server will serve docs for all of the packages in your dev tree, regardless of whether they have a go.mod yet or not.