User blog comment:FairyRaven/Fairy Tail Chapter 336: In Order to Live Today to the Fullest, Review and Commentary/@comment-77.195.192.240-20130624072334/@comment-2214433-20130624083132

There is no path (or shouldn't be) because there are multiple timelines, according to the image I linked above. Future Rogue arrived from the 2nd timeline, Future Lucy arrived from the 1st timeline, at the moment they are creating the 3rd timeline. Changing things in the 3rd timeline - such as destruction of the gates - can only create a 4th one, but there's no way it will affect Future Rogue because he arrived from the second timeline, it's literally a different universe with different events and characters at this point. Because the gate in second or first timelines wasn't broken, both Lucy and Rogue are able to arrive.