Strange Bedfellows

Strange Bedfellows is a main quest in the Fallout 76 add-on Wastelanders.

Quick walkthrough
Talk with Rose. Find David's trophy in Pleasant Valley cabins and find the AI holotape near Ripper Alley. Return to Rose and reprogram the holotape at Solomon's pond. Return to Rose again, and transmit the holotape from relay tower LW-B1-22. Return to Top of the World and clear out the Scorched from the mezzanine. Talk to Meg to finish the quest.

Detailed walkthrough
After speaking with the Vault 76 overseer and learning of the two major factions in Appalachia that have come into the area, the settlers and the raiders, along with a request to deliver the Scorched Plague inoculation to them to protect them from becoming Scorched themselves, the overseer suggests speaking with Rose back at the Top of the World to figure out how to get in good with the raiders.

Upon speaking with Rose about the raiders, she suggests locating the trophy that belonged to former Raider and Cutthroats leader David Thorpe. By showing that to the Raider leader Meg, it would ensure the player characters would be in good with the Raiders. Rose also requests finding an A.I. program that David had used to make her to remember Rosalyn by. After finding the trophy in David's room and searching the room to find a postcard that suggests Rosalyn's memorial is at Ripper Alley, Rose contacts the player characters to make sure they know where they are heading to find the memorial and get the A.I. program.

Upon finding the shrine on a small ridge overlooking the West Tek research center, watch out for a deathclaw matriarch that might be guarding it. Retrieve Rose's A.I. program from the chem case on the altar, and Rose will contact the player characters again, directing them to Solomon's pond to find the equipment necessary to repair the program.

Travel to Solomon's pond, deal with the enemies outside, possibly floaters, and access the terminal in the basement, only to see it is password encrypted. Luckily, Agent Kensington, a glowing one feral ghoul, will be outside. Kill it and find the password holotape on the seat of the nearby portable restroom. Using the password, access the terminal and request to repair the holotape. Once done, report back to Rose at the Top of the World.

Return the holotape to Rose, and after accessing those blocked memories that David locked down on her, she reveals she needs one more holotape from Arktos Pharma, David's old workplace, before she can make contact with Meg.

Head over to Arktos Pharma to find the holotape. Aside from some low-level robots that guard the building (protectrons, eyebots and Mr. Handies), the holotape can be found at one of three locations on the third floor, possibly the trash can in the conference room in the corner. After listening to the conference call between David and his co-workers, take the holotape back to Rose at the Top of the World.

Once she has it, she has one more request. Upload the holotape she gives you into relay tower LW-B1-22, and that should enable her to make contact with Meg and the Raiders. Head over to the relay tower, take out the super mutants guarding the tower, just beware of those carrying miniguns, and use the terminal normally used for calling in supply drops with the US government supply requisition holotapes to play the holotape Rose gave the player characters. After hearing David's voice calling out to Meg, Rose calls again, requesting the player characters back to the Top of the World to clear out the second floor mezzanine before Meg gets there.

Once the Scorched have been eliminated, Meg and two Raiders serving as her bodyguards arrive. Speaking with Meg, despite best attempts to convince her of the threat the Scorched pose to her raiders, especially regarding the Scorched Plague, she only agrees to have her raiders inoculated against the Scorched Plague after the player character checks out an assault on the Scorched being done by her lieutenant Aldridge in the Toxic Valley, west of the Philippi Battlefield Cemetery.

Upon arriving at the scene, there are several Scorched prowling the area and a scorchbeast corpse lying on top of the trailer where Aldridge has sheltered. After taking them out, enter the trailer and find Aldridge there, wounded, but alive. After telling him of what could happen to him and there is no cure to becoming a Scorched, the player characters can either kill Aldridge themselves if they choose the right options, or spare him. Sparing his life has him ask that the player characters tell Meg he fell to the Scorched so he can see whatever fate has in store for him and he can go out on his own terms.

Return to The Crater and report to Meg about what happened to Aldridge and his team, and she'll agree to allow the Raiders to be given the inoculation to protect them from the Scorched Plague, completing the quest.