There isn't a lot of mystery to the headline, so let's just get to the GIF:
If I had to guess, the argument was about fire. How it's made, why Gonzalez keeps the secret for himself, and how Werth could get his hands on some. But an alternate explanation might have to do with a double off the bat from Joaquin Arias in the top of the first. Apparently Gonzalez wasn't thrilled with the effort from Werth on the play.
Pretty sure Roberto Clemente with Evie's time-stopping powers wouldn't have nailed Arias, but it was a pretty weak throw. Both players are going to be on the Nationals for a long, long time, so figure it out, fellas.
Surprisingly, the Giants could not get Arias home from second on the inning, so the play didn't really matter.