You know Magne, Arthur is on Twitter. If you do have the chance you could potentially ask that question days before the event takes place, which is next Sunday.
I've tried asking question 3 before, but to no avail. It irks me that they confirm Maria's name, then seemingly ignore any other requests to provide the names of any other characters.
In fact, if not for Earwig providing those modelsheets here on ECC, we wouldn't have 8 or 9 names that we do now. If the other character names are ever going to be released, it will most likely be here on ECC. (Unless they give the names in an episode, which would be preferred by far )
Maybe they don't have the modelsheets available at the time. We all have to wait. Besides, we can easily figure out who Sharon, Mark, Dawn, and Alex are. It's pretty simple from what I see.