I was following satnav
Oh dear, oh dear, how often do we see this in an OPs narrative ! using a satnav in London or indeed any major city these days is fatal, because they are never up-to-date. YOu might say "but I only updated it a few days ago", Yes but it is the underlying geographic date the various satnav apps use that can be very out-of-date. The video shows you driving without any hesitation past the clear "Flying Motorbike" signs which mean "No Entry for motorvehicles". The signs are qualified by a sign below giving exemptions to the restriction.
The restriction applies Mon-Sat 9am to 5pm.
Does your friend not have a car, because one would expect some warning about access to Maltings Place
Were you unaware of what these signs meant ?
Just looking around with GSV, I began wonder how anybody at all can ever drive to Maltings Place during the day, as here is the sign at the other end of Fulmead St : -
https://maps.app.goo.gl/Sm4KyhAXds7oSgQ96and at the roundabout at the other end of Imperial Road
The whole place is some kind of fortress against motor vehicles !
I suppose there must be some entrance street but which one is it !
Perhaps when submitting representations to the council you ask which streets allow access to Maltings Place during the day !