My recollection is a little different; there were numerous, vague suggestions about the possibility of the camera/mount contributing to the injury but nothing more than that. I don't remember, and can't find, a conclusive finding that it did.
Interestingly, I did find reference to some research by the TRL into the possibility, commissioned by the BBC.
https://www.bbc.co.uk/safety/resources/safetynews/whatsnew/helmet-cams
Here is an excerpt:
Testing Protocol and Safety Standards
During the summer of 2015, BBC Safety commissioned the Transport Research Laboratory (TRL) to investigate and report on the potential effects that mounting a mini-camera may have to a helmet’s safety performance i.e. the change to head injury risk. A range of commonly used climbing helmet types were tested (hardshell, hybrid and EPS foam). The cameras were mounted at the front, side and top of these helmets using either sticky mounts or head-bands. The testing protocol was principally based on that in BS EN12492:2012 (the safety standard which all climbing helmets are required to meet to enable their sale within the EU), BS EN1078:2012 (the equivalent safety standard for helmets sold to cyclists and skateboarders) and EU Regulation 22.05 (the equivalent safety standard for motorcycle helmets). These standards helped define a protocol for measuring the transference of energy to the ‘head’ during standard impact challenges and set the level above which the helmet would be considered to have failed the test. Further injury thresholds, defining a >50% chance of either a fracture to the skull or loss of consciousness for less than 1hr, were also identified from scientific literature to provide further comparison.
Study findings and conclusions
The results were a little surprising. We had anticipated that the placement of a solid object on the helmet would not only provide a single point of impact on the helmet but would also significantly increase the rotational / acceleration forces on the head when it ‘caught’ or impacted on inclined surfaces. The results were expected to be an increase in the transference of these impact forces to the head, potentially sufficient to exceed, or ‘fail’, the injury threshold of the standards. But this wasn’t the case. In fact, in not one of over 70 tests on various helmet types, mounting types or mounting positions did the presence of the camera cause the helmet to ‘fail’ the injury threshold standards. And this wasn’t solely because the camera broke away on impact (as claimed likely by the manufacturer), because this only happened in approximately 40% of tests. It turns out that, as seen on high speed film, when struck by a heavy weight from above, or when a helmeted head-form is dropped from height onto a solid surface, the deformation of the camera mount seems to actually absorb some of the energies involved, meaning that the camera mount may be providing an additional layer of protection to the head in most, but not all, tests.
