I kill the mob, but don’t get credit for it.
The bounty is Torraxteria.
I cant finish Malmouth without more reputation and I cant find any Aerther Vanguards to slay. Now I can’t continue with bounties because I am stuck on e that won’t clear when I kill the mob.
you need to exit to menu and re-enter the game for the bounty targets to spawn again
Yeah I did that three times. Finally the 3rd one gave credit. Odd, spawned same spot all 3 times too.
There are also lots of Aether Vanguards south of Homestead as well as in Commander Lucius dungeon at Fort Ikon.You can also get lots on the way from Fort Icon to, and inside the Necropolis.
aren’t those just counted as normal aetherials reputation wise??
edit - yup, just cleared all, 0 vanguard rep, they are all just normal aetherial corruption faction
you sure you werent’ killing Valaxteria (fixed spawn) ? - and maybe on the way 3rd time you got Torraxteria since she ca4n spawn in path while you go to Vala 
Really late reply., sorry. I was killing the bounty one, but didnt get credit until the third kill. It also happened with the the eastern body wagon. I had to do it twice to get credit so I could complete the quest.
Mike and Gnomish: As for the ‘vanguards?’ I read that the hero and champ mobs count as ‘vanguards’ and you get 35 rep and 75 rep from them.
nop,
like i said above i did a clear, this includes champs, heroes and bosses, and base game/fort ikon and necropolis aetherials do not count as vangard
you might be able to get vanguard spawns from Aetherwarped totems tho, but otherwise, there are no sources of aetherial vanguard kill rep until you reach malmouth - they are all aehterial corruption faction related
super easy to tell on my guy since it has 0 vanguard infamy regardless how many heroes or champs or bosses i keep killing in fort ikon/necropolis (just did another to confirm)
I forgot about the totems. Yeah those could give rep too. They do spawn name mobs very often, if not every time after 50. Good call.
fastest way is still just to do malmouth runs
attempting to get an off chance vanguard spawn in a totem outside malmouth etc is gonna be a 100x slower than just moving to malmouth and do kills there, preferably while doing resistances bounties too
That’s what I did till I got the rep to get to the last quest. I did three more clears after I finished the area.