Get media attachments from specific tag

<?php
    $args = array(
        'post_type' => 'attachment',
        'posts_per_page' => -1,
        'post_status' => 'any',
        'post_parent' => null,
        'tax_query' => array(
            array(
                'taxonomy' => 'post_tag',
                'field' => 'slug',
                'terms' => 'logo'
            )
        )
    );

$images = get_posts( $args );
if ( $images ) {
    foreach ( $images as $image ) {
        // Get the parent post ID
        $parent_id = $image->post_parent;
        // Get the parent post Title
        $parent_title = get_the_title( $parent_id );
        // Get the parent post permalink
        $parent_permalink = get_permalink( $parent_id );
        // Get image caption

        $logoimg = wp_get_attachment_image( $image->ID, 'Work Gallery' );

        $posttags = get_the_tags();
            if ($posttags) {
                foreach ($posttags as $tag) {
                    str_replace('-','_',$tag->slug . ' ');
                }
            }

            echo '<aside class="work_item" data-id="id-' . get_the_ID() . '" data-type="' . $posttags . '">';

                echo '<ul>';

                    echo '<li>';

                        echo '<div class="img_wrap">';

                            echo $logoimg;

                        echo '</div>';

                        echo '<ul class="work_meta">';

                            echo '<li class="work_title">';

                                echo ' ' . $parent_title . ' ';

                            echo '</li>';

                            echo '<li class="work_item_content">';

                                echo ' ' . get_post( get_post_thumbnail_id($post->ID) )->post_excerpt . ' ';

                            echo '</li>';

                        echo '</ul>';

                        echo '<ul class="work_features">';

                            echo '<li class="lightbox">';

                                $attachment_id = $post->ID; // dynamic attachment ID
                                $image_attributes = wp_get_attachment_image_src( $attachment_id, 'full' ); // returns an array

                                echo '<a class="work_lb tooltip" data-id="' . get_the_ID() . '" title="view in lightbox" href="' . $image_attributes[3] . '" rel="prettyPhoto[mixed]">';

                                    echo 'Lightbox';

                                echo '</a>';

                            echo '</li>';

                        echo '</ul>';

                    echo '</li>';

                echo '</ul>';

            echo '</aside>';

        }
        wp_reset_postdata();
    }
?>