If custom taxonomy exist on post?

You can use has_term() to check if a post is in a specific term.

if ( has_term( 'reel', 'filter', $post->ID ) ) {
    get_template_part( 'loop', 'work_feed_reel' );
} else {
    get_template_part( 'loop', 'work_feed' );
}

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)