Looking at the event in the files, I don't see any reason why it can't fire for Najd:
Nothing in there about being African. Just make sure you have positive relations with the Ottomans though, or else you won't get to reform your government,
Code:
trigger = {
has_dlc = "Art of War"
OR = {
government = tribal_despotism
government = tribal_kingdom
government = tribal_federation
#government = tribal_democracy
}
NOT = { has_country_flag = sultanate_request_choice }
legitimacy = 90
stability = 3
OR = {
full_idea_group = economic_ideas
full_idea_group = innovativeness_ideas
full_idea_group = administrative_ideas
}
religion_group = muslim
151 = {
owned_by = TUR
}
TUR = {
religion_group = muslim
has_ruler_modifier = khalifah
NOT = { war_with = ROOT }
}
}
Nothing in there about being African. Just make sure you have positive relations with the Ottomans though, or else you won't get to reform your government,