It would be good PR if they gave it away for free, but, creating additional cinematics, bringing back the voice actors, planning out the endings, costs money, and a lot of it. I, personally, do not mind paying more for answers to the amount of questions we all share.
Of course, if this was all a stunt to begin with, than I'd assume all of the work has been done already and a free DLC should be released.
Only if they have to actually go back to the drawing board and work up this alternate ending would I be alright with handing over more money. But with the way things ended, and the vast amount of questions, I still can't believe they don't have something hidden up their sleeves.
I will be shocked if they finally come around to deny there ever was, or ever will be, additional endings. It'd be really sad as I'd like to talk to the writers and find out if what we saw was the only thing they envisioned for the ending. As an aspiring writer/artist I want to clean it up and write ridiculous amounts of fanfiction to appease my needs. lol I'm only a hobbiest when it comes to writing, and it seems us as fans are able to imagine better endings where others have agreed already would be amazing.
How could these writers, who have spun such an amazing story with such amazing characters just come up with what we saw? The only answer I could give that is EA pushed them in a particular direction in which they had no other alternative. Or, EA told them to save the final ending for some other medium they wish to publish it in, or wanted to be unique and raise the bar on how to break the fourth wall (and ****** off a lot of people till word is released lol). *Seriously, if this was a stunt to indoctrinate the player as well I will be so happy! Bravo, really!

I'm all for trying new things.*
I've gotten a bit off track here, but all I'm saying is, if it's already in the bag than release it to the fans for free. If it requires more time to work on it, and it wasn't previously planned already, than I'm open-minded to paying for a satisfying conclusion to one of the best stories I've ever been lucky enough to experience.