First : There is a problem with Coils, since almost nobody runs it. It failed, and failed hard despite the amount of work provided by devs.
Secondly : You can't asking for vocal for a pug, i talk about really pugs in global (grab 5 randoms and go) not some sort of group when you are all in each-other friendlists. Good luck pushing people to go in vent when frenchies are using mainly mumble and spanish people raidcall. And good luck having the better communication and exact pronunciation while explaining the tactics to one russian, one french, one aussie, one scottish and one italian guy ;d
You can't also make a progression group for coils with a PuG. Definition of pug is, except of the leader, others players can change. I'm pretty sure you're experienced in progression raid, and progression raids are viable only if you don't change players each day. That's why only OPR can have progression in T4 and clearing T3 regularly despite of the nerf of TAS cause you have people entitled to one class and coming each week.
Coils is a guild-dungeon or friend-group dungeon. Knowing that, it reduce drastically its popularity and it remains like this forever if nothing changes from funcom's devs PoV. Only dungeon like this is Ti an an district but at least it loot some accessories better than T4 ones (wings). Which is fairly surprising cause usually people start to QQ that K6 stuff better than raid one is sorta game-breaking and push funcom to out-nerf them
But tbh who cares, when pvers got bored of kithans HM they just leave the game.