With every theory on Rey's parentage in the new Star Wars trilogy comes a different use of a quote by Daisy Ridley from Time Out in 2016:
I thought a lot was answered in The Force Awakens. Then after the screening I went for a drink with my agent and everyone, and we were chatting away and I realized that 'Oh, in their minds it’s not answered at all.
This has been taken to mean everything from "Luke is obviously Rey's father, just look at the parallels" to "Han's fatherly treatment of Rey is clearly more than just niceties," to "Maz Katana said Rey's parents are never coming back and we should take that as fact."
That last idea is commonly swept aside by Rey Skywalker subscribers (myself included, admittedly), but the recently released Star Wars Battlefront 2 adds a bit more fodder to the theory than can be ignored. Now, the idea that Disney would reveal something so heavily debated through a video game a month before The Last Jedi is released sounds absurd at first, but upon putting together all the facts, it was enough to make this fan reconsider.
Warning: Spoilers for Star Wars Battlefront 2 ahead.
The new game's story mode follows two newcomers to the Star Wars canon, Iden Versio, and Del Meeko through the end of The Return of the Jedi to the beginning of The Force Awakens. The pair begins the game as members of the Imperial special forces trying to retain control of the galaxy after the second destruction of the Death Star, but quickly turn their backs on the Empire and join the Rebellion when Iden is ordered to destroy her home planet.
The following missions carried out for the Rebellion, including some establishing a close relationship with Leia and Luke, climax in a battle over Jakku as the war is finally ended and Iden and Del are finally free to live a normal life.
That is, until the game jumps forward thirty years and Del is tortured by Kylo Ren as Kylo searches for the map to Luke, just before The Force Awakens. Turns out Lor San Tekka, the guy who gave Poe the map, was actually given the map by Del. Kylo orders Del to death and Del is berated by his former friend from the Imperial forces for leaving the Empire for "fatherhood," a jab that is never addressed or explained further.
So, two Rebel pilots close to Luke and Leia fell in love on Jakku, had a child, and presumably continued that close relationship with at least Luke afterward, since Del is found with Luke's map. The cleanest jump to make here, if this is not just a random side story for the game, is that Del and Iden are Rey's parents.
Obviously, Rey being a Skywalker is still a top contender for most for the Best Parentage Theory, but if Rey isn't related to the Skywalkers at all, this would be the way to explore that story. There isn't enough space in the films to give more than a few brief references to Rey's parents if they don't already exist in the Star Wars canon, so created an entire game to tell that story would work well. Luke or Leia could easily reference their relationships with Del and Iden while speaking to Rey about her past, and the movie could move on.
At this point, Rey not being a Skywalker would be the biggest plot twist of all and might even open the door for a different Skywalker hero in the form of Finn or Rose, two characters whose parentage is just as much a mystery at this point.
Of course, there are some holes in the theory. This doesn't explain why Rey was left alone on Jakku as a child and, although Del does find the Force while on his mission with Luke, it doesn't explain why Rey is so strong with it. It doesn't explain why Kylo Ren seems to know Rey and murmurs, "It is you," when Rey beats him to Luke's lightsaber in The Force Awakens novelization, either.
In that case, this entire game could be a red herring, meant to encourage new theories before The Last Jedi comes out. But, until then, we've just got one more theory to indulge.