To be honest it sounded like that to me too. It's very hard to differentiate between some honest clumsy phrasing and fishing for a payout, and the "clarification" doesn't help with that since it could also be an excuse to save face.
Maybe with text snippets, but I don't see how somebody can listen to the conversation and come away with the idea that the dev was blackmailing anyone.
I don't understand, what is the threat on Christian's part? His project is being killed, that's not a threat but something that is actually happening. He suggests that they pay him a small fraction of what he has cost them to shut down without compromising the reddit API as a whole. What's the threat, that he keeps operating? That's not an option, they are FORCING him to shut down.