Hello madsravnjensen,
Is that in the Southern Mining Tunnel or the Western? Also, what quests have you completed? I can honestly say that I have never encountered the issue where Roderick was placed inside of the wall? It could possibly be due to not all the appropriate game files being downloaded from Steam.
I would first attempt to reload into your most previous save. If it is then still an issue possibly re-download the game. If nothing seems to resolve this and it is still an issue it would be very much appreciated if you attached the save file to the forum so we could take a look at this issue.
Thanks,
Tyler