I really doubt he was fired since he just accepted a job with the biggest game developer in the world. It says so right in the OP. Don't take your unwillingness to read out on me.

So, the writer and the director have left the studio...

I wonder if they still say that the release date won't be affected.

A Japanese game would be canned (their gaming industry works different).

Time to panic?  Of course!!

Something awfully fishy going on

This is either a crap time to get into the games industry or something is seriously wrong at Sony, chances are this isn't related to the layoffs as a sony restructure, but he probably disagrees with some things or stuff that's going on, such as amy hennig dismissal etc.

So two of the main Uncharted staff have gone. Druckmann and Straley can't head Uncharted and Last of Us 2/new IP surely? Hope they have some capable people to step up

c'mon badger, believing the sony-owned media. You should know better.  
It's more likely honorable Sony disapproved of his last game and punished him by giving him the window seat.
He probably couldn't take it anymore and left.

Why are all these talented people leaving? They should fire the Japanese developers instead!

My thoughts exactly .... Dont know the topic, but its a good guess that it was the amy thing, but something internal is definitely going on.