Meredith lived around 6000 years. It's sad that he spent a lot of time imprisoned in the Tower, but he allowed the Tower magicians to experiment with human sacrifices etc., etc.
Now he's doing the right thing and after that it will be time for him to leave this world...
Lidusis on the other hand was neglected by his parents, bullied by his brother, bullied at school.
He has been happy only short time in his life (as a child with Hadelio siblings and then with Rood).
So he deserves to survive and live a happy life after that.
The same in fact goes for Rood and Kiel. I hope that Yong will let them all survive.