I don't know how much more clear he could have been then to say fact checkers are hired outside verified fact checkers.  So yes there is a system in place.  One thing about Facebook is people also serve as fact checkers by requesting of Facebook to check to something that has been posted.  With billions of customers posting at god knows what kind of rate the hired fact checkers are not going to catch everything but you can bet your bottom someone else will and that will get it placed on hold for review.  

What the left wants is censorship first of every bit of information out there as long as it doesn't pertain to the many falsehoods it puts out on a daily basis.