Congrats on the new feather-babies. Props to you for rescuing!
I hope they are adjusting well, but if you need any help with taming and such, this is the place to be!
It's going to be harder than having only one cockatiel, since they have each other already, and since they came in pairs, chances are they're already bonded. If you want to bond with your teils, you can try taking one in a different room away from their cage, so you can spend some one-on-one time.
Since it sounds like the pair from the basement haven't had much interaction with people, expect them to be a bit more of a challenge. I will tell you though, it will all be worth it.
I once had a cockatiel adopted from a rescue, and he was absolutely terrified of people. After some time working with him, he became a total cuddle-bug!
He still had his quirks, as he only liked being pet while he was on my chest.
Since there's dogs, too, then it would be best to bring them to a room without the dogs, so it doesn't stress them out. Dogs, being natural predator animals, can be quite stressful to a cockatiel, which is a natural prey animal. After they feel comfortable enough with you, then you can try socializing them with the dogs. It is possible for them to get used to dogs, but it may take time.
With that said, welcome to the forum!
I do hope you enjoy it here.