Ambassador

During the playthrough, I was somehow convinced that Lorenzo would stay with me until the end of the game; I focused on him... Alas... Varens was very unlucky with his skill choices.

Exactly the same thing happened to me! I developed Lorenzo so well, I practically created a terminator out of him!))
However, as I already said, after his shameful defeat, he will flee to a dwarven tavern in the underground city, and we will be able to give him a second chance ;)