My quest is also bugged. Got guest from Ron, then went and talked to Piper to finish "Story of the Century" and then went straight to vault 81. Got in via persuasion. Walked right in, talked to overseer, and then tried to talk to Cedric. All Cedric says is Hello. Katlin only says hello and Rusty is all vanilla speech. Have not done hole in wall quest, did Austin's tour after failure to get Cedric to talk. I did/do have schematics in hand and it makes no difference. I tried dropping them and talking, picking back up and talking and nothing new.
I am using the following mods in this order:
Pick up your Power Armor!
Armor and Weapons Keywords Community Resource (AWKCR) (XB1:ALL DLC)
Settlement Electricity Overhaul
Unofficial Fallout 4 Patch
Workshop Framework
Sim Settlements 2
HUDFramework
Better Sneaking by Draoga
Mute Those Perks!
Indoor Fast Travel - All DLC
BioHazard Suit
Global Stash (Connect all Workshops and Workbenches)
Truly Overpowered Perks
[XB1] Color Map Collectibles
(Official) Caliente's beautiful bodies enhancer -CBBE- Curvy AIO
Wattz - Fission Battery
Amazing Follower Tweaks FO4 Edition
Quest Manipulation Program Holotape (Automatron Patch) [WIP]
Quest Manipulation Program Holotape (Base) [WIP] {Reupload}
[XB1] Commonwealth Landlord
[SMM] Settlement Menu Manager
[XB1] Craftable Display Shelves
Face Texture Glitch Fix A
Legendary Modification
One Minuteman Radiant Quest at a Time by Crimsomrider
The Mobile Mechanic XBOX ONE - Portable Workbenches and Junk Breakdown
Automatron Unlocked [XBOX ONE]
[XB1] Pieces of Power Armor Crafting Mod
Girly Animations
Nanosuit Female Edition no Katana Version
Power Armor Redistribution XONE
X1 Jacq's NOT Default Eyes
[XB1] Ponytail Hairstyles by Azar
Quick Hack and Pick
Locksmith - Lock Your Doors 'n' Containers!
Zella's Hair Dye Collection
More Craftables (Xbox 1)
Sanctuary Bridge Fix
Craftable Power Armor Frames (Xbox 1)
[XB1] UCO Base Game (core component of United Clothing Overhaul)
Improved Automatron Robots
Fusion Core Crafting
Changeable Armor Sizes - Xbox 1
[XB1]Realistic Ragdoll Force
Cheat Terminal [Xbox One]
SA80 (L85 & L86) British Rifle
[XB1] Laurent's Robot Skins [Custom Automatron Paintjobs!]
Universal Crafting Mod
Unlock all Companions by SKK [Xbox]
Rise of the Commonwealrh for Sims Settlements 2
Aside from the SS2 mods, I've been using the rest of these mods for a while through multiple characters with no apparent issues. I've only just started having issues after putting SS2 in the mix.
On top of this quest, I also have issues with Sanctuary, I cannot send anyone there from other locations and I cannot assign anyone to the city planners desk. Tells me I do not have control of Sanctuary.
Any and all advice is welcome. Loved the first SS mods and was super thrilled when I came across SS2. Now if I could just play through everything.
Here is a list of completed quests in the order completed, top being the first one.
War Never Changes
Out of Time
Laying Foundations
When Freedom Calls
Plotting the Future
If I Had a Hammer
Casting a Line
Scavver's Delight
Returning the Favor
Suburban Disturbance
Well Well Well!
Sanctuary
Let Sleeping Dogs Lie
Hub of the Problem
The Coolest Cat
Story of the Century
Vault 81
I also am playing on the Xbox Series X, if that makes any difference at all.