My question is: Has the filming production for Iris 2 started? If not, then CCM is simply overreacting. I don't like businesses and their marketing strategies, but then again I'd like to be as fair as possible. The previous news article never mentioned anything about Soyeon BEING in the cast. The official in mentioned article said that they're "positively considering to join the cast", not "offered to join the cast".
Yes I like the fact that CCM made a response to this article, but what they are claiming to be the rumor simply did not exist to begin with. The was nothing definite about the previous article. What CCM should've done is just clarified that Soyeon has yet to received any cast offer for Iris 2.
Now, if Iris 2 filming production has started, then it's an entirely different story and I'd side with what CCM has done.
-My 2cents