In actuality, Jin Rou didn't want to interfere. After all, it was a battle that only the young elf had the right to fight against. However, there was a foul play that transpired, and it looked like no one had managed to see it. If not for him, the young elf and his future might have have been sabotaged already.
Remember, Asner was an elf and although his lifespan was longer than humans, the potential of humans were far wider than his. As someone who aspired to be an ancient emperor, this kingdom wasn't his final destination. It was the whole new world outside of this place.
And now, someone pulled a bad joke of making him fail the test? Jin Rou could sense a conspiracy between the lines. In fact, you didn't need to be smart to deduce it this way.
Asner's father was boiling with rage. But he managed to control it. He was waiting if what the young man said was right or not.