I am also having a similar problem. Did you ever find a solution for this @coatmaker618 ?
My htaccess contains the same stuff as yours. But I’m on nginx, while you’re on apache. I don’t know if that makes difference but wanted to note that in case it was pertinent to my issue.
I see a lot of threads commenting on this issue in all of them they seem to indicate that redirect information about the web dav etc are supposed to be held in the apache or nginx configuration directly instead of in the .htaccess of nextcloud? But the .htaccess of nextcloud 16 ships with this information in it’s htaccess so there must be something missing?
Here’s a thread I found that seemed to indicate the issue was related to the apache or nginx settings: Caldav and carddav error resolving