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.
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The Goldsmith's University Student, who doesn't want to be named, was assaulted as she crossed the road in Tottenham, north London.
The toddler was taken to hospital along with two girls, aged five and six, and a woman who was also injured.
London's smallest pub is set to start pulling its first pints in a shed in Greenwich.