I can't find Scandi's original mail, so I dock on here. Yes, the hyoid bone and if I remember right, also a finger bone was missing. Both are small bones, but finger bones hang on often longer with skeletal remains if no bigger animals are around because they are connected by relative short and strong tendons to other bones while the hyoid bone hangs free. It's not really unusual to find the hyoid missing in skeletal remains in the open when little animals are around.
And, Maddalenasgirl, when you ask your anthropologist, please include in the question also the timeline, the area, the water conditions (as in sometimes wet, sometimes not so wet) and the local fauna in your question. Otherwise you could maybe cause some wrong impression, the anthropologist would base his/her judgement on.
And on another side note, four bones, I would have expected missing are still there or at least not reported missing. Two inci and two stapels. Those are small bones in the inner ear. I am not sure whether I spelled them correct in English, but well, you could look them up. Those normally when decomposition is progressed enough, fall into the skull. The tricky thing is, if you later move the skull, they also fall out as easily. If the SCPD really has them, it would prove, that nobody moved the skull unless it was maybe a little turn in situ or something, but for sure no transport.