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
Police have released CCTV images of a man seen close to the scene of one of the attacks.
A 20-year-old man who died in a triple stabbing outside Parsons Green Tube station has been named by police.
David Jones was responding to London's Fire Commissioner who said the term 'fireman' was outdated and should stop being used.