"Fake" El is an Angler, so it would depend on whether that can faction can be set to hostile. I suspect not, because it would block too many quests.
Sri-La Village isn't the only location Salty El may be found. Here's a teaser: Image: Els Fishing in Fields of Niuzao
It appears that "pool invasions" can occur in many specific locations in Pandaria. First one just sees more pools form. But eventually (overnight so far, so hard to be sure) a larger monster pool spawns. These invasions are tracked by a group of Anglers, including Salty El (although the precise NPCs involved changes slightly from location to location), who move from place to place.
More details in due course - this will take a while to fully research.