Hildibrand content cut to ONE quest

[Musashidon]

I doubt it. It was just a thing they probably did once, like making Ivalice required for Bozja, or CT required for MSQ.

The relic area will be Shades' Triangle, so I'm sure it'll be related to that this time.

you have to remember the relic quests are done in pairs aka arr and heavenswards was roughly the same menial tasks then stormblood and shadowbringers was exploration content and endwalkers was manderville so the chance of them doing again isn't completely out of the picture.