Most installs from Facebook Mobile ads never even open the app once (Yes even Once).
If you read the post from the same guy, you will notice he actually targeted to People who play word games on mobile.
Companies like King and others have VERY competent teams of digital media and analytics experts, as well as the engineering resources to implement VERY advanced tracking.
They would most definitely not be spending the large sums they are if they were not very confident in the return it gave them.
Working as intended.
I've also tried some things that don't really work on facebook at all. I think as marketers, we need to be nimble and quickly figure out if a given platform is where our audience lives. Iterate quickly and do statistically relevant test sizes before you commit a massive budget to anything.