In tournament Tournament the top 3 teams had the same points, 2 wins and 1 loss, the same report on goals scores/goals conceded (5/2).
They results were this way:

Team 1 0-2 Team 2
Team 2 0-2 Team 3
Team 3 0-2 Team 1

1. Team 1 2-0-1 5-2 6 pts.
2. Team 2 2-0-1 5-2 6 pts.
3. Team 3 2-0-1 5-2 6 pts.
4. Team 4 2-0-1 0-9 0 pts. (the manager lost all the games by technical lost)

My question is what's the criteria to split the teams in this case?

random

As stated above, if teams are locked on points as well as goal difference, then it is randomly decided who moves through, as far as I can tell there are no better options.

Regards,
Mutt