So, to sum up, some lads and I have been investigating the commits in each tgz so far of sango_project (aka xy_project) and so far there's no evidence of southern kalos actually being implemented beyond the planning stage, even in early xy commits dated like 2011
Any "leads" like
>>56719464 were just false alarms and the route map models turned out to just be close to final in terms of layout
Beginning to think that they scrapped a lot of cool shit before they even implemented it in the actual game
Evil AZ, Battle Island, Mirage Island, South Kalos, etc...