Flipping conspiracy nut Joe Rogan is not a good source for anything.
If you reverse image search that image you will find a description of this:
It's just a survey of funeral mounds. People burying their dead, that's why its all over the place.
Gareen was the name of the imperial family much like Walashma & Sa'ad Din .
Ajuuran was not what they called the state, it was a local nickname for taxing administrators that levy taxation from the populous and coordinating labour. It comes from the Arabic word Ashuur (Taxation) = Ashuuran basically.
It's similar to what is described in Futuh in these passages:
Then the emirs and the sultan replied, motivated by fear of the imam Ahmad,
may the Most High God have mcrcy upon him, โWe agree with what you have said
to us about this matter, and we will not oppose you.' Thereupon the imam Ahmad
sent one of his administrative officers to the [better off] people of the country, to
the cattle owners and to the farmers, to collect the alms tax from them.
Other times it's not just administrative officers that are sent out to collect tax. You read Imam Ahmed coordinating agricultural production directly:
The storyteller; may God have mcrcy upon him, says: So the Qurโanic teacher Abu Bakr reached the imam Ahmad who was in Zarba, sitting and giving commands to agricultural workers, โDo this and do that'. He knew nothing [of this matter] and had heard no news. Then the Qur'anic teacher Abu Bakr handed over their letter, and he read it and understood its contents. The imam then said to the Qur'anic teacher Abu Bakr. โReturn to them and tell them that what they want is vile, but let them do what they desire. I shall leave the country to them/
Locals didn't call their state Awdal or Mogadishu either, those were name of cheif commercial cities that outsiders knew them through. Their administrative capitals where centered somewhere else.