I don‘t know if I‘ve understood your problem correctly, but you can create individual groups in DokuWiki from your ad-users by using the virtualgroup-plugin:
https://www.dokuwiki.org/plugin:virtualgroup
Also, you can use ad-groups directly in the acl-manager.
Please notice that groups maybe are named a bit different from the names in your ad (only lowercase characters, no whitespaces, ...).
The best is to search a user which is in an ad-group you want to use in the user-manager. There you will see how the ad-group is named in DokuWiki.