It's not that Kael, Draneg, and the other demigods didn't feel affection for their family, apprentices, and subordinates, but they weren't so attached as to give up their chance to ascend as gods for them, like Zaros, Elidyr, and even Lugia.
They were about to tell him what they knew about the situation that had occurred in the seas since they had received information from Zaros, so they wouldn't be so mean as to not tell him, because, in the end, he would find out later.
However, at that moment Elidyr arrived at the place. Like the others, seeing the city, he felt sad, but the reason was different. If the other demigods were sad to arrive late and lose the opportunity to gain favorable points from Andrew, Elidyr felt sad because he understood Zaros' pain.
