Je ne doute aucunement de la véracité des cartes. Je doute qu'elles ai été ouverte dans un booster dominaria. Sauf si c'est effectivement un fait volontaire de wizard mais ça va totalement à contresens de leur politique de spoil des sets.
D'autant plus qu'on entre en période de spoil Battlebond.
Je vais essayé de me renseigner auprès de mes contacts chez WotC, mais si ce n'est pas intentionnel, c'est probablement ce même cas de figure:
"One day, a player goes to his local shop and buys a pack of Magic 2013. In it, he sees a copy of Rootborn Defenses. Magic booster packs usually have ten commons in them; none of those commons, though, tend to be from the next unreleased set!
He goes to the Internet to share his news. There is much skepticism. The question everyone was asking was "How could that even happen?" He ends up contacting Wizards and we ask him to send in the card so we can figure out what is going on. Once we are done with our investigation, we had Erik Lauer sign the card (he designed it) and sent it back with a Selesnya banner signed by all the members of the Return to Ravnica design and development teams.
So, how could that even happen? Here's my best guess. We print a lot of cards. As such, quite often, our printings are scheduled back to back, meaning the printer will print one Magic product, finish, and then set-up to do another printing of a different Magic product. My best assumption is that the printer in question printed a batch of Magic 2013. After that was done the printer moved onto other projects. At some point, the printer printed an early run of Return to Ravnica. Directly after that printing, it did a reprint for Magic 2013.
When a printing is done, the printer cleans out the hoppers (i.e., where all the cards rest directly after being printed). Every once in a long while, the printer misses a card. Often, things get released chronologically upon being ordered or it's another run of the same product so no one notices. When the Magic 2013 reprint was done, the missed card got scooped up and packaged with the new printing .
And that is (probably) how a Return to Ravnica card got sold in a Magic 2013 booster months early."