There was't much variation in amateur battles and Lu Li predicted correctly.
Team Screen Protector successfully killed an opposing Mage. The Three Healers weren't able to heal in time, which showed the Team Ursae Majoris was less mechanically skilled.
In reality, Ursae Majoris was a mercenary group that specialized in quests and trainings.
Their top players were mostly players that specialized in completing quests and levelling others up in the Wild. Their equipment was good but they never had time to compete in arena because they were busy making money. Their previous wins were most likely because of luck.
If both teams were mediocre at PvP then the team with the better equipment would obviously win.
The name Screen Protect was lame, but most of their players spent a lot of time in the arena. Even though they weren't professionals, they were still able to strategize and take out this questing team.
And so, Ursae Majoris lost.