Bo Katan can’t take the darksaber from Din, but she could take it from Sabine?
Well, Sabine didn’t win it in combat like Din did, she just found it on Dathomir. Just like it took a full season to explain why Din couldn’t remove his helmet, I’m sure they’ve thought up a good explanation for this as well. The darksaber also made its first appearance in Filoni’s series so I’m absolutely sure Favreau went through it all with him as he wrote this episode.
Grogu’s fate is to be killed by kylo? Wonderful.
There’s so many ways this can go so I don’t see why this has to be the case. As mentioned before its quite vague how many were killed by Papatine/Kylo so there could be plenty of them still around somewhere. Also there’s the whole Ahoska world-between-worlds thing, Grogu might still be a Whills, etc. etc. Who knows what they’ll end up going with all of this.