Update @arminunruh I actually found this, and this worked for me!
https://www.forge12.com/en/blog/change-the-primary-block-in-wordpress-multisite/?unapproved=3304&moderation-hash=87ad761a398fcc0027c32c6867d303c9#comment-3304
The only thing is, the URL is still rothkuo.com/two instead of just / and I'm unable to change it in My Sites > Network Admin > Edit Site > Settings. And the permalinks still go to rothkuo.com/two even though initially when you go to rothkuo.com it all works. I don't mind it too much but if you have a solve for that, I'd love to try it.