Hello everyone,
I'm having the same problem. I'm using the steam v3.03.1047 (fysical copy)
So i played around 25h, been to the city and surroundings doing quests and when i encounter hiravias i get through his dialogue untill the promt come's up whom i'm to swith out for him joining my party and when i switched him with another character. Either both characters are gone from my party or everything stays the same (with my textbox saying that hiravias joined & then left the party for some reason)
I tried multiple times, different save file's, going through different dialogue line's from hiravias. I even tried going to the keep afterwards and swithing characters there. But that doesn't help at all. He just doesn't want to join.
And sometimes when hiravias "joined my gang", he's on a different spot on the (same) map. And when i talk to him, its like his in my party because i can ask him oppinion about my mission/friends etc. One time he was even in the keep map somewhere around the western bridge instead of going to the inn-like place with the different rooms.
I left a save file here:
Its the first link (i think) thats just near the guy
http://www.mediafire.com/download/v345dk8wgnci12d/45664303-c627-41a0-9347-a0a8af263449+quicksave.savegame
http://www.mediafire.com/download/awt2olwhd60w8ek/45664303-c627-41a0-9347-a0a8af263449+autosave_1.savegame
Here you can see some screenshots if it could help (i tried changing him with aloth):
http://www.mediafire.com/view/sr4dws3ulvo6e41/PillarsOfEternity_2016-07-17_21-42-58-18.bmp
http://www.mediafire.com/view/1thjo18btmyg12f/PillarsOfEternity%202016-07-17%2021-42-40-56.bmp#