First step: Make sure both Xboxs have correct title update(easiest way to do that is by going to storage an looking for title update of the game you are choosing to match the other Xbox if both have the same than that is not the problem)

Second step: If you are still stuck, Make sure ping patch is enabled in dashlaunch on your rgh this will stop your Xbox from being able to choose not to connect because of the usage of Internet already. If you don't know wht dashlaunch is look it up and try to find a link on google for it it allows you to have freestyle dash start up as default and allow some other cool things((: Make sure Dev link is disabled in dashlaunch settings also(:

Third step:If you still can't connect try making your regular Xbox dash the default one and check the dashlaunch and freestyle setting very closely to see if anything would throw off you connecting.

Message me if you still can't connect(: