I did these quests for the Decor items, here are my findings:
I was able to get The Ruby Feast! within the tall building with the round-room main-floor (entrance at 48.5 50.0 within [zone=13862]). This started the very short quest chain, so check for this quest first unless you didn't play in Dragon Flight. Inside the building it was given from a floating banner that is near the wall at 46.3 45.3 (next to the large parrot wearing a pirate hat named Polly Roger). This sent me to [npc=189479] and I got this quest All Tea, No Shadeleaf which will finally sent me to [npc=185778] to do this quest Warm Away These Shivers.
If you're like me and (unfortunately) didn't play during Dragon Flight you will need to unlock the quest chain. After A LOT of research and deciding to do a bunch of quests to try to have this quest-chain (from the floating banner) be obtainable. Be sure to be careful if you are doing the quest skips (possibly miss out on Mogs, Rep, a nice story, and maybe more. So do your research before activating quest skipping) with [npc=198720]. But from what I gathered online it was required to do this [storyline=5568 domain=www] until you complete The Last Eggtender (This seems to be the quest that unlocks The Ruby Feast!.)
Recap and further info: by obtaining The Ruby Feast! and completing it I was able to do:
Edited some wording and added info.