Here is the letter and pictures they sent back:
First of all may I thank you for returning the hat to me for inspection.
Although we carry out weekly testing of our products both in house and at the BSI, inspection of helmets involved in real life impacts give us a better understanding of how the helmets component parts manage the energy involved.
Your helmet is a Ventair Deluxe Jockey size 56cm or 57cm. The outside surface of the helmet has slight scuff marks to the left front bottom edge above the left eye and temple area. The Shell has not been damaged.
Upon further inspection having removed the shock absorbing polystyrene liner from the outer shell it is quite evident that this hat has been involved in a high energy impact. The shock absorbing polystyrene liner has been reduced from 20mm to 15mm in thickness and has become soft at the bottom edge in the area described above. You can see this damage in the photographs which show the liner has crushed on the inside and outside. There is no visible damage to the Glass reinforced outer shell.
The damage to the liner is consistent with that of the polystyrene being crushed between the wearers head and the impact surface outside.
Champion Manufacturing (SH) Ltd