template_include not loading -instead goes to index.php

in order for the discography rule to work, I changed the rule from:

add_rewrite_rule( 'artists/([^/]+)/discography/?$', 'index.php?album_artist=$matches[1]&discography=yes', 'top');

to this :

add_rewrite_rule( 'artists/([^/]+)/discography/?$', 'index.php?artists=$matches[1]&discography=yes', 'top');

What the original rule was doing was pointing to the Artist’s Name and not the Artists custom post type, thus failing to redirect to the template. Thanks a lot to @RachelCarden for this.