When you are looking for something like 80g (as is the maximum of the graph), then the head would move something like 4 cm between two frames, which suggests to

When you are looking for something like 80g (as is the maximum of the graph), then the head would move something like 4 cm between two frames, which suggests to me, that you probably want to have a lot more than 100 fps, since you want to get a good handle on the highest accelerations. On the other end of the scale, the positional error from the camera sensor is something like width of frame / horizontal resolution which should give you something in the mm range, and it seems possible to get head tracking in the same order of resolution, which should limit your acceleration measurement for low acceleration. Overall, probably doable but you are replacing a 30c accelerometer with a multi year research project.