https://en.wiktionary.org/wiki/battle_royal#English
https://en.wikipedia.org/wiki/Battle_royal
books.google.com search "battle royale" in the 19th century, you'll see talk of ladies squabbling and how to conduct a mass cock-fight
Here, the title qualifies Battle Royale with "Death Match" implying that this Battle Royale is to the death.
> ...and they are not organized into teams. Here, the title qualifies Battle Royale...
but in this incident they were organized in teams
Anybody is free to use any word in way they want. However, using words in common ways will help prevent confusion. For example, "battle royale" (or "battle royal") is mainly used to refer to "A fight involving three or more individuals, teams, or factions; fought until one person, team, or faction is left standing" (from Wiktionary). Using battle royale to mean something else will lead to confusion among most English speakers.
> but in this incident they were organized in teams
And this particular discussion about the article was about the misuse of the term Battle Royale, specifically the use of term to describe combat with two teams instead of many.
Does it? Wrasslin' has had Battle Royals as long as I've been alive and conscious and I'm sure -- although I can't find the reference now -- that English bare-knuckle boxers used to have Battle Royals in the mercantile period for non-trivial money.