Whilst I would not bet my mortgage on Walter being wrong I offer the following.
I am in my 37th year in the RAF. In that time I spent 14 years as an Avionics Technician, 10 years as a Puma Crewman and the last 13 years as a Herc Loadie.
In that time one of the things I have learned is that secrets very rarely stay secrets.
There is more chance of me winning first prize in the Euro Millions lottery than there is of all the folk who would have HAD to have been involved in what Walter suggests keeping quiet for this long.