And the article does not say / make apparent where this information is from.
Basically he said that 2 of the 3 engines didn't start up correctly, and caused the booster to hit the water at a few hundred miles per hour.
I'm guessing the dive into the water was purposely missing the barge when it detected the problem, as they have spoken about this capability in the past when they were first making attempts at landing the rockets.
He also said that as long as they have the footage, and it's cool looking, they will post it somewhere!
This should have been a 1-3-1 style landing burn where it lights up one engine, then 2 more to slow it down, then drops down to just 1 again at the end. In this case it sounds like the the outer 2 engines didn't start up right, so it came in way too hot.
They also have said that the center core of FH is basically a new design from the ground up, so it makes sense that they had some problems on it's first landing.