Nah, Like most other devs of these types of games that get very popular... he simply made more than enough $$$ to no longer concern himself with finishing what he started. It is currently a plague in this genre, sadly. I personally never believe when all theses devs come with these lame sob stories, 'i was sick but now better' 'my dog died' 'I was trapped on a Somali pirate ship for two years'

. Im too cynical to buy that crap.
The truth is... They will eventually be back to stringing folks along with remakes or shallow content updates when they notice their bank accounts have dipped just far enough.