Unless there is some new info, WoW "Delvings" is nothing like FF14 "Trusts". "Trusts" are going through actual instances with NPCS (plural). "Delvings" is running around (On Land) solo or with 1 or more players and an NPC (Singular) tagging along (Kind of like our Chocobos).

I think of WoW "Delvings" like a slightly more advanced LOTRO "Mission/Delving" with a tag along NPC added in.

Would it be nice to swap in players for NPCs here? Sure, but lets not conflate reality with fantasy in other MMOs.