So I finally bought Fallout 3, GOTY edition, but played most of the main quest without installing any DLC. During this span I somehow let Dogmeat get killed. If I were to get the Puppies perk (if I can still get it?) would this still grant me infinite Canine Companions? That is the impression that the wiki gave me and I hope that's the case.

When you have the perk, and dogmeat dies, a new pet dog will appear out the front of Vault 101. This will happen an infinite amout of times. However, Broken Steel makes Dogmeat effectively invincible, once he is reborn, he will not die.

The same goes for Fawkes, with Broken Steel both are virtually un-killable.

Unless, of course, you just gas him in his cell

Hence the 'virtually'.

Which I'm really thankful for, given the number of times I've shot at him when fighting Supermutants... He's taken that double-barrel shotgun to the face at least twice now!

I fired the Tesla Cannon twice at him and he lived. He is a walking, talking, laser shootin' tank.

And thankfully he never turns hostile. When I gave him those shells in the face I was worried that he'd turn that Gatling laser on me.. and I wasn't sure I'd survive... I could swear he was left behind at Air Force Adams base when Lyons picked me up in the Vertibird, and he just shrugged off that airstrike while my mod companions Gary and Lucy West went unconscious. Scary!