I've tried the same steps that you described here and when browsing to https://<jmp-server-ip>/xmp/system/versions it's successfull. However when I browser directly to https://<jmp-server-ip> I get an nginx 404 error. There doesn't seem to be anything that sticks out in the nginx logs either.
Has anyone else come across this 404 error?
All of the other steps that are suggested I can verify are correct.
Anyone have any further ideas or things to lookout for troubleshooting?