Anyway I think it was all speculation and there's no truth to the "secret leaks".
I'm skeptical. I assumed RDM would be a fencing tank of sorts so if it isn't, I'd be excited.
The thing that gets me is.. SAM doesn't fit. Stormblood will be Ala Mhigo which isn't Japanese-ish. Doma is but the Domans came and brought NIN so either they will cheaply add SAM as "Oh, no, the Domans also had SAM, they just didn't show you or mention them before." or...I dunno.
All the HW jobs fit Ishgard; DRK were knights who turned away from the hierarchal church-affiliated knights of Ishgard in favor of vigilante justice. MCH were born from Ishgard's Dragonsong war and thus their need for anti-dragon weaponry like Bertha cannons, the had the idea to take handheld guns and empower them with aether. AST, as we play it, is a Sharlayan spin on the astrologians that have been employed in Ishgard forever. AST takes these star readers to the front lines using Sharlayan astrology to heal.
So, DNC? Could fit but it's a stretch. RDM? Same, fencing is more of a French-type thing but maybe, being a European art of sorts, it could fit. SAM doesn't really fit at all, considering how the Emperor looks, it seems like it'd be more of a pre-imperial Garlean art. Perhaps it is and perhaps you will encounter a group of traditional Garleans or something. They have a lot to do to make these jobs fit imo.