I would be very surprised if the 6-day construction includes:
Site setup
Site clearance
Piling or excavation and casting the in situ concrete foundations
Off site fabrication of the modules (which it obviously doesn't)
Installation of the mechanical and electrical services; they must have done first fix, but not sure if they did second fix. Presumably the major items of plant have been installed
Finishes / installation of fixtures, sanitary ware (maybe they are using pods?), etc. internally
Soft and hard landscaping, car parking, roads, pavement, etc. externally
From the video it seems that they constructed the super-structure or 'shell' in 6 days (and they also had the internal partitions installed).
Constructing the super-structure is the most visually productive time of the build because it seems that you have done an awful lot in a short period of time.
My point is that the hotel is far from practically complete.