He knew that the Three Kingdoms even though the stories of their ancient proved to be true, it is not so easy to let go of their throne and kneel upon an Outsider.
The thing about ancient lore and old stories about Asrana is that it is biased toward Asrana. The story is about Him after all which explain the bias.
Arial knows it would not be easy to convince the three kingdoms to accept him.
After all, for the gate to be opened, it is said one have to conquer all the Three Kingdoms.
Those who could do such a feat would be given the location of the Ancient Gate
And such, Arial knows whether he claim he is Asrana or not, the Three Kingdom is not going down without a fight.
The fact that they wanted to steal his fate, tell him what he already knows.
The borders. Suddenly his mind went to the borders.
'Tch' he clicks his tongue.
He is thinking about guarding the borders.