A quick update of the resource(s) by Vamtastic.
hub.virtamate.com
I noticed that nothing in the scene actually had collisions, so I imported them back to Unity, threw mesh colliders on the room and chair, and then re-exported.
Easy peasy.
Add a custom unity asset, select this assetbundle, select the prefab.

Flynns Secret Lab - Environments -
this was a challenge in fixing a few things but got there , created by jvouillon at sketchfab under cc license included is the chair as a prefab and Preview scene

I noticed that nothing in the scene actually had collisions, so I imported them back to Unity, threw mesh colliders on the room and chair, and then re-exported.
Easy peasy.
Add a custom unity asset, select this assetbundle, select the prefab.