Yeah, that really isn't obvious. They might want to add a line in the Quest Log that says something like 'We should go see Yoranus in the Barracks once we get back to Cyseal'.
As for Bertia's quest, some people have reported that it can be finished if you trigger the right dialogue with the mortician. I have personally never been able to complete it in any of my playthroughs. I think it should be enough to have the sheep in your inventory to be able to ask her 'is this your sheep?'. It makes sense for your character to make the connection.
