You might be correct that I'm mistaken wrt the intellectual property of comments. I'm not an IP lawyer and cannot state it with confidence one way or another.

What I feel comfortable stating is however that we have precident for the exact scenario the person I responded to (wanting royalties for a storyline they posted on a social media website) and this precident showed that are least the lawyers of WB were of the opinion that a rewrite outside of any social media platform was necessary.