I still suspect that Scorpion was real, but the sheer amount of (in my mind completely justified) backlash against him may have changed minds about including him as paid DLC, or at least as part of the season pass download set. We'll see, I guess. I wouldn't be shocked to see Zod next though, and then another DC character to round out the (first?) four DLC characters released.
Likewise, as soon as I looked at that character select screen I was instantly hit by the thought that it felt as if there had deliberately been left room for an additional eight character slots, so I wouldn't be at all surprised to see a second set of four, and if Scorpion was real, then I could certainly see Sub Zero (or one of the other MK ninjas) also being originally planned as well.
What I think may happen now is that we'll get four DLC DCU characters in this set, bringing one forward to 'sub' for Scorpion, and then they will have to re-assess how to follow up from there. I can see them either doing a second season for four more DCU related DLC characters, or else they'll release the other two likely already planned for DCU DLC characters individually, with no pass, and later also offer the MK ninja(s) as individual download(s) for those that want it, that way avoiding the situation of forcing anyone into buying MK characters as part of the pass. I just don't see them shelving Scorpion (and potentially another MK ninja), if the work had already been done, or was already well in progress.
Now they may have caught wind in time to shelf the second MK character, and are looking to replace him with a DCU character now, but I would be very surprised if Scorpion doesn't show up sooner or later.
Of course I'm also probably completely wrong, so...