Reer Woqooyi would be muslim and the faqash would have been naked bantu god worshippers
Jokes aside,Scholars still don't understand how exactly Islam spread among the Somali tribes and why no gaalo tribes remain(homogeneous).The story for now is that Islam entered through Saylac,and then from there these newly converted folks who turned into missionaries spread Islam like wildfire in the interior.Not much info on this topic since Somali nomads never write shit down.But from the archaeological findings in Somaliland,Reer Woqooyi would have probably became Orthodox Christian(admixed with that Waaq religon) if Islam was not founded at all due to Ethiopian influences.So basically to answer your question,we don't know what would happen if Islam was founded in the Somali peninsula because we don't how the f*ck we became muslims in the first place.This topic is very complex and probably not suitable for the average guy in this forum. But would love to hear what you guys think.
Saylac has in it the ruins of one of the oldests mosques. It dates back to the 7th century so it's certainly reasonable to think Islam came through there. I think the monotheism in Islam appealed to people (as it wasn't too foreign to them) and the increase in strength of the Muslim world over the next few centuries played it's part. But I think something that is often overlooked is just the numbers. I assume (?) there were less people back them, so when changes did occur they spread faster and quicker and became more permanent as time went on.