Norseman, your article doesn't address the mitochondria results from over a hundred samples, and like you, simply assumes contamination, or what ever suits their own interpretation without any study of the actual evidence.
It is unfortunate that so many of those samples are not available for independent study, but that's not the case for all of them.
Where modern sapiens, neanderthal and denisovans are distinguished, it started in the mitochondria. It wasn't there in the bigfoot samples submitted to ketchum.
If the hybridization continued from the time of denisovans, it would be possible that a single mitochondrial lineage prevailed. Meaning multiple human ones, because the crossing never stopped.