I still maintain that these individuals were probably remant east cushitic speakers on the red sea coast who migrated here.I think you're getting things a bit mixed up, T-L208 or if we're more specific T-BY181210 is Dir proper, it's not a minority lineage it equates to 10-20% of the Somali male population, and it wasn't 1 singular man but a family unit that arrived in Northern Somalia around 2,200 years ago or older, possible alongside J1 blacksmiths, they brought camel culture as Nortern Somalia was drying up, the rendille share a lot of camel lingo and they separated from proto-sam. The lineage was super successful compared to its sibling that stayed in Arabia.
"According to linguist Bernd Heine, this separation occurred between approximately 300 BCE and 200 CE, when the Proto-Sam language divided into Western Sam (Rendille) and Eastern Sam (including Somali and Boni) branches ."
People hear Isaaq, Gadabuursi, Isa, Gurgura, Surre, Biimaal etc.. and think they are standalone, but in reality they are a sub sub sub of Dir, it's just ancient and spread across the winds, some have completely separated, others absorbed by different Somali confederations, and some have even become Oromo, when you're one of the oldest and most spread out.