I have a question about the song "Burn." I'm not sure if this is the right place to ask? But I'm gonna give it a go

I was just reading the Ellie/Ed Sheeran post and someone mentioned Ellie lied about co-writing Burn. I've always been confused about this because there is an interview where Ryan Tedder says he wrote the song in Chicago. He doesn't even mention Leona recording it. Also, Leona's and Ellie's versions have the same exact lyrics except for one word. Then I saw a video of Ellie (sorry, lost the link, but it was on youtube) saying that she wrote Burn in Las Vegas. Below is the link to the interview with Ryan Tedder. What do you guys think? Did she co-write it or not? I'd be very grateful if someone could shed some light on this for me!
http://m.billboard.com/entry/view/id/84237