A Mediterranean couple sought in connection with Williams' death is now considered a "red herring" after further police inquiries.
Organisers of the ladies fashion course Williams' enrolled on in secret will give statements to the inquest too.
The lawyer for MI6 says calling corporate witnesses will "paint a picture and set the scene".
Two experts have tried to reconstruct how Mr Williams could have got into the bag and locked it - The coroner says he wants a live demonstration in court.
The issue of whether or not Mr Williams could have got into the bag and padlocked it from the inside "goes to heart" of inquest the coroner says.
More top news
Patricia Al from ran up the monster debt after using her O2 mobile in Turkey.
The position, posted on the British Monarchy website, pays £16,000 a year for 20 hours a week.
Police are hunting for a passenger seen on CCTV after a 15-year-old boy was attacked and left with a punctured lung.