Re: Do we take "fanon" too literally?
There could be a bolian serving as the Commandant at SFa without the Bolian homeworld being a UFP member.
Ro Laren served in Starfleet before Bajor was a member world, in fact while Bajor was still under occupation by the Cardassians.
Still, the Commandant of the Academy (or any flag officer for that matter) is likely going to be a Federation citizen. Similar to how people are allowed to serve in a country's military today without citizenship in that country, but they aren't going to be flag officers or running the military academy.
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