Same logic applies to his father, Robert Boutflour, who writes notes involving the possible use of the silencer, without knowing that Ralph Bamber had even purchased a .22 aqnshuzt rifle with a silencer...
The relatives know about the silencer (in my opinion) before they were entitled to know about it. Not only that, but they appear to have known about its possible use in the crime long before they knew that such a silencer belonged with the anshuzt rifle...
I have narrowed it down to them being told about the anshuzt rifle, and its silencer, by them coming into contact with Anthony Pargeter, at a time when the relatives thought that the silencer that David had got his hands on belonged to Anthony Pargters .22 (Bruno) bolt action rifle. Yes, they thought it belonged to Anthony, and that first silencer got handed to cops by Peter Eaton on the evening of the 12th August 1985, before relatives got time to speak to Anthony Pargeter about it. It was only later, on the following month, when cops went to speak to Anthony Pargeter about his bolt action rifle, and he made a witness statement to Essex cops that he always had kept his rifle at whf but had the habit of removing the bolt and taking 'it' home to Buckinghamshire, so that no-one could fire it in his absence, that Anthony became aware that cops had got his silencer (the one Peter Eaton handed over to DS Jones). It was immediately after this visit to see his bruno rifle, that Anthony Pargeter went to see the other relatives to try to find out whether or not, cops had been given his silencer, or the one belonging to Ralph Bambers anshuzt rifle...
This is what caused David Boutflour to return to the scene to search for the second silencer (September, 1985)...
When he found it, he must have showed it to Anthony Pargeter, only to have it confirmed to him, that cops had got the wrong parker hale silencer. They had been given Anthony Pargeters silencer, not the Bamber owned one...