All the creditor has to do is show that you have in all probability received the demand - service through the post unless by recorded delivery is usually frowned upon by the court - but if you make an application to set it aside - you are effectively admitting you received it.(posted 7990 days ago)There is no denial slip as such attached to the demand - particulars as to how you can oppose or settle or secure for it are contained within the wording.
You could always sit back until you get the Bankruptcy petition which HAS to be served on you personally - if you then say, "never got a stat demand" and apply for the BP to be set aside, all you do is delay things and the court would likely put you to proof you did not get it rather than the creditor to prove you did.
Best advice is let them make you B - don't put obstacles in the way - go to the court with details of all your income and expenses and capital assets, sit in front of Judge, he will make the order, then you wait for the Official Receiver to contact you, interview over telephone usually, then you do as the OR tells you.
Lots of people have been through this, look at www.debthelp.co.uk