I'm not sure whether anyone has tried this yet, but I just contacted the support team as to this issue and they escalated the matter to the studio/senior support. Perhaps nothing will come of it, but we can only hope!
can't believe this isn't fixed yet--reported this months ago to the tech support
At this point they seem technically unable to fix it: so since we've been waiting so long with this feature broken, the devs should just let us claim any city, regardless of content--it's not like we'd use that to get access to content we shouldn't at this point.... it'd make the game usable right now instead of "Abandonville" where all the cities in a region are abandoned but unclaimable
