Board Thread:Questions and Answers/@comment-25893370-20170428201515/@comment-25893370-20170429195700

Found this note on this wiki, in the Dreamworld section:

"In an update on 11 December 2016, access to Dreamworld was removed from mobile. However, King claimed that this removal is temporary, but the duration currently remains unknown.[1"]

I guess thats why it cannot play on Fb Gameroom, as they updated it to the "mobile version"