I doubt that Bro-Speak or Dude-Speak are actual dialects.  Maybe they qualify as Pidgins?  It’s been a while since I did any reading on such stuff.

If I remember right, though, a Pidgin can develop into a Dialect, given time and restricted outside influence.

So, somewhere in the Baja peninsula, there may be a small group of dudes who are building up a Bro-speak that will one day be discovered by Etymologists who will be both gleeful to have discovered it, and wildly disappointed that any human beings can communicate via a language that’s been truncated to the point where it employs only seventeen words.

…Twelve of which would be either general exclamations or adjectives, depending on context.  The paper the Etymologists publish would be “Gnar.”