I attacked him (and "killed" him) when he was trying to talk to me about getting him as a shout. Now, he won't come back. Can I force spawn him or am I just S.O.L.?

Well, you killed him while he was trying to help you... If I were a unkillable dragon, I think I'd give you the finger and fly away. Sorry, but it's safe to assume you S.O.L

way to go dude.

Where do you find him after you punk him down in the Cairn?

Right outside the boneyard, he is waiting for you.

This is what happened to me, I really hope there's some way to get past this. I killed him before I realized he was trying to talk to me and then ran away.

wait, what? he activates dialogue with you.

That's what I figured, but literally right out of the loading screen I shot him with an arrow, his health bar disappeared, and I continued running toward the Soul Cairn exit. I didnt even know I was supposed to get a shout from him until ages later reading it online. There was no dialogue that stopped me and I can't find him anymore in the Soul Cairn.