Cpl Bayliss was Supernumary Crew, not a passenger. Rules for passengers are different.
The carrying of the 'circus' in the back seat was a cheap way of getting 'crew chiefs' from 'A' to 'B'. In no way could Cpl Bayliss be regarded as Supernumerary Air Crew. You can call him what you want the questions remain the same.
DV