What I do know is that the shackle link and the offending bolt are still present, and can be "wiggled" if desired to check that the link hasn't been clamped onto the shackle.
Many thanks for that information. However, I do note that MB Special Information Leaflet 704 and 704A (brought out after the accident) make it clear that no freedom of movement checks are required for seats with a gas shackle.
DV