Although they knew they had time, they also understood that it was limited and that was not just about the dragons. The demigods also knew of Andrew's existence and such a large attack was evident to everyone.
Purgatory was clear that the demigods of other races would not sit back and make a move. Even though their methods were different, the goal was the same, to achieve divinity.
Purgatory wanted to do it with the resurrection of the fallen god and the demigods placed their hopes on Andrew as a candidate for god. Although Andrew did not have those means, no one was clear about it, even so, Purgatory had to consider these enemies.
It would not be strange if the other demigods came to help to gain Andrew's favor, in fact, it was expected that they would do so and that was where Dustas and the kingdom of Tripia came in.
