Zuhl3156
The best way to deal with the big bloated charcoal ghouls is to blow their legs off. Then they can't reach you. It'll still take a lot of ammo to kill them but they just lay there on the ground squirming like a worm. The Doctor showed up as 'green' in VATS but I killed her anyway. I just picked up a magazine somewhere that gave me a 'Turrect Hack Perk' but I couldn't hack those turrets in Covenant. I couldn't repair the old turrets or knock them off of their pedestal either. I was outside planting new turrets and I heard Cait shooting it out with someone so I went inside and killed the only person I saw. When I looted him it said "Settler". Oops, I think I killed my first Settler to Covenant.
Been down that road with those ghouls many a time like that. And that "I dare you" look that they give you after both legs are gone. I just smile and blast away. LOL
The old turrets were and are a pain because you can't do anything with the remains except watch them smoke.
Remove the bodies from inside Covenant and drag them down to the river and leave them there. After a period of time you can loot them again. Just allow a little time to pass before doing so again.