Part of title duplicating but not sure how to remove from code – help?

You’re on a page and if we read through the list of conditionals it should hit this one specifically:

elseif( ! ( is_404() ) && ( is_single() ) || ( is_page() ) ) {
    wp_title( '' );
    echo ' - ';
}

It will also hit the below conditional in the next set:

else {
    bloginfo( 'name' );
}

Given page Test Page we should see Page Name - Company Name but the parent Twenty Fourteen theme has this filter on wp_title():

function twentyfourteen_wp_title( $title, $sep ) {
    global $paged, $page;

    if ( is_feed() ) {
        return $title;
    }

    // Add the site name.
    $title .= get_bloginfo( 'name', 'display' );

    // Add the site description for the home/front page.
    $site_description = get_bloginfo( 'description', 'display' );
    if ( $site_description && ( is_home() || is_front_page() ) ) {
        $title = "$title $sep $site_description";
    }

    // Add a page number if necessary.
    if ( ( $paged >= 2 || $page >= 2 ) && ! is_404() ) {
        $title = "$title $sep " . sprintf( __( 'Page %s', 'twentyfourteen' ), max( $paged, $page ) );
    }

    return $title;
}
add_filter( 'wp_title', 'twentyfourteen_wp_title', 10, 2 );

Notice that it is also appending the Website Name to the title ( directly after the feed conditional ) which is why we end up seeing the company name twice. You can comment out the above line to remove the duplication.

function twentyfourteen_wp_title( $title, $sep ) {
    global $paged, $page;

    if ( is_feed() ) {
        return $title;
    }

    // DONT Add the site name.
    // $title .= get_bloginfo( 'name', 'display' );

    // Add the site description for the home/front page.
    $site_description = get_bloginfo( 'description', 'display' );
    if ( $site_description && ( is_home() || is_front_page() ) ) {
        $title = "$title $sep $site_description";
    }

    // Add a page number if necessary.
    if ( ( $paged >= 2 || $page >= 2 ) && ! is_404() ) {
        $title = "$title $sep " . sprintf( __( 'Page %s', 'twentyfourteen' ), max( $paged, $page ) );
    }

    return $title;
}
add_filter( 'wp_title', 'twentyfourteen_wp_title', 10, 2 );