There's even a former Xbox employee in the ResetEra thread on this subject saying marketing wouldn't do it like this 😭😂
Nobody has provided a rebuttal other than they want it to be Fable, it "sounds" like Fable (lots of things "sound" like Fable such as The Great British Bake Off and many Rare IPs share a similar tune) and it has a trail (a common thing in mystery videos styled like this) which we will ignore is the exact same colour and style of the Xbox Showcase Branding, Lol.