The atlas holds this study because of a question it does not answer. Myrrh appears throughout the religious literature of the ancient Near East and the Mediterranean, in temple incense, in anointing oil, in burial preparation and in trade records, and the ancient sources name it as a single commodity. Which species that commodity was has never been established.
This investigation does not establish it either, and its own account is careful on the point: the result stands for the modern trade and does not reach the ancient question. No securely dated archaeological myrrh from any trade period has been analysed the same way, and until some is, the species behind the myrrh of antiquity is unestablished.
What the study does is remove an assumption. Because the modern commodity is demonstrably not one species, there is no longer any warrant for supposing that the ancient one was. That changes the status of the question rather than answering it. It is why the atlas records the ancient identification as unknown, meaning that nobody holds a position that could be argued against, rather than as debated, which would imply camps and a live dispute. The study is what the unknown points at, and what would close it is plain: sequencing of residue from a securely dated ritual or funerary vessel.