It wasn't in - house, there's a few of them about in off the shelf theme varieties. Some of the media on this might have been more in house though.
A quick Google, it was made by Alterface.
They're the same people making the new complex sounding Popcorns Revenge trackless dark ride at Walibi. If the reliability of this much simpler ride was as bad as I recall we should all wish Walibi the best of luck with that one!