Forked version of the Vidyard WordPress Plugin which adds support for AMP: https://knowledge.vidyard.com/hc/en-us/articles/360009993593-Using-the-Vidyard-for-WordPress-oEmbed-plugin

vidyard-wordpress-plugin.php

<?php
/*
Plugin Name: Vidyard WordPress Plugin
Plugin URI:  http://vidyard.com
Description: Makes it easy to embed your Vidyard videos into WordPress. (Forked version which adds AMP compatibility.)
Version:     1.1.1
Author:      Vidyard
Author URI:  http://vidyard.com
License:     MIT
*/

wp_oembed_add_provider(
	'#https?://embed\.vidyard\.com/share/.*#i',
	'https://api.vidyard.com/dashboard/v1.1/oembed',
	true
);

wp_oembed_add_provider(
	'#https?://play\.vidyard\.com/.*#i',
	'https://api.vidyard.com/dashboard/v1.1/oembed',
	true
);

wp_oembed_add_provider(
	'#https?://.*\.hubs\.vidyard\.com/.*#i',
	'https://api.vidyard.com/dashboard/v1.1/oembed',
	true
);

/*
 * Filter oEmbed response for rendering videos on AMP pages.
 *
 * Example oEmbed response:
 * <script type="text/javascript" async src="https://play.vidyard.com/embed/v4.js"></script>
 * <img  style="width: 100%; margin: auto; display: block;"  class="vidyard-player-embed"  src="https://play.vidyard.com/LtJJqfyHztRQP2PRYoQ4gf.jpg"  data-uuid="LtJJqfyHztRQP2PRYoQ4gf"  data-v="4"  data-type="inline"  data-width="640"  data-height="360"/>
 */
add_filter(
	'embed_oembed_html',
	function ( $cache, $url ) {
		$host = wp_parse_url( $url, PHP_URL_HOST );
		if ( ! preg_match( '/\bvidyard\.com$/', $host ) || ! function_exists( 'is_amp_endpoint' ) || ! is_amp_endpoint() ) {
			return $cache;
		}

		if ( ! preg_match( '/data-uuid="(\w+)"/', $cache, $matches ) ) {
			return $cache;
		}
		$uuid = $matches[1];

		$v = '4';
		if ( preg_match( '/data-v="([0-9.]+)"/', $cache, $matches ) ) {
			$v = $matches[1];
		}
		$width = 640;
		if ( preg_match( '/data-width="(\d+)"/', $cache, $matches ) ) {
			$width = (int) $matches[1];
		}
		$height = 360;
		if ( preg_match( '/data-height="(\d+)"/', $cache, $matches ) ) {
			$height = (int) $matches[1];
		}

		$cache = sprintf(
			'<amp-iframe allowfullscreen class="vidyard-iframe-%1$s" src="https://play.vidyard.com/%1$s?v=%2$s&amp;type=inline&amp;disable_popouts=1" sandbox="allow-scripts" layout="responsive" width="%3$s" height="%4$s"><amp-img placeholder layout="fill" src="https://play.vidyard.com/%1$s.jpg"></amp-img></amp-iframe>',
			esc_attr( $uuid ),
			esc_attr( $v ),
			esc_attr( $width ),
			esc_attr( $height )
		);

		return $cache;
	},
	10,
	2
);