Fallout – In Mothership Zeta: How to destroy the generators in the Cryo Lab in Among the Stars

I know it's a huge pain, but have you walked the route the slaves take from the Temple of the Union to the Lincoln Memorial? The NPCs have been known to get caught on terrain glitches. Sometimes, interacting with one of them can resolve the issue.

I'm kind of worried that the slaves actually did arrive, but "timed out" while waiting for you to tell them it was safe to head up to the Memorial. I don't think there's a way to conclusively prove or disprove this theory, unfortunately.

Later in the game you will acquire weapon schematics which specify these parts. ie. you will be able to make weapons out of them.

While there's little point hoarding hundreds of each item, you will find it useful to make multiple copies of each weapon since that lets you repair them when they deteriorate. So it's useful to hang on to some of the junk. The rest you could sell.

See here if you want to see the weapons you can make and what parts you need to make them.