Can't speak to the accuracy, but I do notice a couple of interesting things:
The Bazrangid dynasty in the Banadir was Persian, very early (224 in Iran) and was centered at Kilwa. These folks would have preceded Himyar in Mogadisho and gives credence to the "Seat of the Shah" theory with respect to the name.
The Yibir (Ibro) and Midgaan (Gaboye) cover most of the North in 650 AD. The Isaaq and Darood don't form until 12th-13th centuries.
According to Sada Mire, the north coast was part of the Himyar/Saba cultural area and the full area of Somaliland was once ruled by Axum, when that empire conquered and ruled Yemen.
https://link.springer.com/article/10.1007/s10437-015-9184-9