I'm not familiar with the specifics of HaYonim Cave, but in general I do think a major issue is that what people do with their corpses is ritualized and often c

I'm not familiar with the specifics of HaYonim Cave, but in general I do think a major issue is that what people do with their corpses is ritualized and often class/role centric. So what exactly did they do with their dead? Who knows. And that's really the problem. These measurements all come down to make some fairly substantial, and unprovable, assumptions. And there are the other issues you also are not considering, and are generally not considered. There are a practically infinite number of reasons that developmental correlations between contemporary humans and groups 10,000+ years in the past might no longer hold. Yet we have to assume that they do. Again, it's another fairly substantial, yet unprovable, assumption. And in general that's the problem. We have to make a whole lot of optimistic assumptions, but if even one is off then everything is completely thrown off. This is the reason I tend to take pre-historic anthropology with a grain of salt. For that matter even post-historic anthropology tends to often be full of questionable science. For instance one big piece of news was the discovery that a piece of Viking burial cloth, in Sweden, contained Arabic script and references to Allah. The problem is that it was later discovered that the script it was allegedly written in had not yet been invented at the time of the corpse's burial. That such a 'discovery' was not the first thing that was checked before racing to publish seems to be an unfortunately common occurrence in these sort of sciences. It goes without saying that you should try to disprove your hypothesis, not prove it. Only then when you've completely failed to refute your hypothesis should you begin to considering the possibility of its correctness, given available information.