How to use the filter in yoast seo to redefine a default image for only certain CPT that is used in the open graph tags.

filter-opengraph-image-per-posttype.php

<?php
/**
 * Filters the image used in social meta tags added by yoast seo plugin.
 *
 * This is used to set a default social share image for various post types.
 *
 * @param  string $image string containing link to image that is used in tags.
 * @return string        string containing maybe updated url to image
 */
function pwwp_filter_yoast_opengraph_image( $image = '' ) {
  // make $post available in local scope.
	global $post;
  
  // this is the name of the cpt we want to modify.
  $cpt_to_modify = 'your-cpt';
  // this is the id of the media library item we want to use.
  $media_id = '33333';
  // this is a partial of the url to the globally defined default image.
  $string_match = '/img/logo.php';
  
	// check we're on the post type we want to set a default image for.
	if ( $cpt_to_modify === $post->post_type ) {
		// if there is no featured image set it to a specfic one
		// NOTE: there should ALWAYS be a url as there is a global default set,
		// this is just in case there isn't. For wahatever reason.
		if ( ! $image ) {
			// since no image is defined set it to the media item we want.
			$image = wp_get_attachment_url( $media_id );
		} else {
			// if the image url has this partial string then it's the default
			// and we want to override it for setting this CPTs default.
			if ( strpos( $image, $string_match ) !== false ) {
				// set the image to the specific media item we want.
				$image = wp_get_attachment_url( $media_id );
			}
		}
	}
	return $image;
}
add_filter( 'wpseo_opengraph_image', 'pwwp_filter_yoast_opengraph_image', 10, 1 );