Thanks for the illustration Cyclic Hotline. Hard to otherwise understand the 'innards' when seen from the outside.
Below are close-ups of the damaged tail rotor as seen in the TV footage. The 'paddle' with pair of blades that was on the side closer to the tail boom was the one that failed. There is no obvious sign of the graphite spar left sticking out of either side of the 'rubber boots' still on the inboard side of where the blades had been. So perhaps their graphite spar failed at the point where the pitch control rod passes through it? Either that or the spar failed in two locations either side of the pitch control rod but inboard of those 'boots' (which seems less probable?). If the spar or rotor attachment had fail further out, then I might have expected the unbalanced remaining blade and spar would shear off the pitch control link when they parted. Clearly, that didn't happen and the pilots presumably still had control of tail rotor pitch (for the remaining blades).
From the TV footage, it seems one of the remaining blades was also damage at leading edge near its attachment lugs(?):
Here is a photo of an intact S-76 tail rotor including cropped to just its hub assembly:
