This is not malice, but incompetence. People who have very little experience in grappling do not understand how easy it is to break the arm in certain positions. The particular position of this teen’s arm is exactly the same as what is commonly known as a “kimura”:
While this street fight begins strangely slow (possibly due to intoxication), one person applies an omoplata and breaks the arm/shoulder.
A submission taken to completion is not a “submission”. It is a break.