Another Project Zer0 video was published last night - linking to the website and a supposed ARG puzzle.
The video appears to make use of imagery and location of the Bethlem Royal Hospital building, which is a world-leading NHS psychiatric hospital. The video appears to be attempting to play on the history of the hospital, where it was notably one of the worst asylums that existed - albeit in a completely different location within London.
It feels very unlikely that Thorpe would run another asylum themed event after the previous media issues and general changes in public perception to how mental health is presented. Further to that, it is impossible they would have permission to use imagery of an existing NHS hospital in this manner.
I asked Thorpe and the more active Merlin Annual Pass twitter accounts if they could confirm this as fake. I got a quick response below, which says it is, but it's quite possible they were referring to the wrong thing, mostly because I haven't seen a response from Thorpe. I asked for clarification this morning, but that hasn't come yet, so I can only assume that this is the response that they meant.