OK, now this is interesting I think. I couldn't link to the Washington Post's telling of this story on the main page, but it differs from the one linked here from the Washington Examiner.
In the Post they tell of America doing a kind of end run around the demands of Turkey in order to support the Syrian PPK Kurds in the Raqqa attack.
You should be able to link to the WaPo article from this one:
https://www.washingtonpost.com/world/na ... 8be96dec00Myself I'm leaning more towards the WaPo telling on this one.