I can confirm that the following worked for me (PC console commands). At least I was able to continue with the quests advancing themselves. I did not choose the vampire path and was banished. type the following into your console: coc DLC1VampireCastleGuildhall You will load into the guildhall, then open your console again and type: prid 03002b74 moveto player The first part moves you into the guildhall, the second references Serana and moves her to you. I am using Skyrim v1.8 (Steam patched this morning)