https://imgur.com/a/ekd2fca
This was my command
/mvcreate ocean normal -g CleanroomGenerator:9|stone|3|dirt|7|sand|9|water

I am guessing it was a Spigot bug. I updated and reran it. World gen was nice.

Sounds like this is no longer an issue. Feel free to re-open if that's not the case.