What a horrible thing to have to experience, I'm so sorry that happened to you.
It sounds like you miss your birds a lot and your fiancée is willing to take another chance, that happened years ago so I say go for it. First reinforce your coop and run, get a camera, get a strong lock, get a guard dog if you can...anything you can think of to deter predators (2 or 4 legged).
You enjoyed them before, you shouldn't be denied the privilege of enjoying them again. Just take every precaution possible.
Good luck to you!
Thank you so incredibly much <3 I have most of what you suggested and I think I'm willing to go for it. To be honest, he loved them too and wants to see peeps grow again ^^