I'm pretty sure someone else awhile ago had the same issue of the cutscene just not being triggered (no teleport involved), but I couldn't find the topic, and don't recall if or how it was resolved.
There may be a way to give yourself the helmet, though it would be better if support can fix the cutscene.
Activated developer console (only tested with the demo).
In XP the saves are in the folder
C:\Documents and Settings\ %username% \Local Settings\Application Data\Divinity 2\Savegames
or in Vista / Win 7
C:\Users\ %username% \AppData\Local\Divinity 2\Savegames
You may need to set Windows Explorer to show hidden files and folders (
XP, Vista,
Win 7).
