Kludge for removing hook in WordPress when you don't have the exact callback object.

remove_hook.php

<?php

/**
 * Kludge to remove hooks when I can't pass the precise object instance.
 *
 * @param string                $hook_name The filter hook to which the function to be removed is hooked.
 * @param callable|string|array $callback  The callback to be removed from running when the filter is applied.
 *                                         This method can be called unconditionally to speculatively remove
 *                                         a callback that may or may not exist.
 * @param int                   $priority  The exact priority used when adding the original filter callback.
 *
 * @return void
 */
private function remove_hook( $hook_name, $callback, $priority = 10 ) {
	global $wp_filter;
	if ( isset( $wp_filter[ $hook_name ] ) ) {
		$hooks = $wp_filter[ $hook_name ];
		if ( isset( $wp_filter[ $hook_name ]->callbacks[ $priority ] ) ) {
			$hooks = $wp_filter[ $hook_name ]->callbacks[ $priority ];
			foreach ( $hooks  as $hook ) {
				if ( is_array( $hook['function'] ) 
					&& ( $hook['function'][0] instanceof $callback[0] || $hook['function'][0] === $callback[0] )
				) {
					$main_instance = $hook['function'][0];
					remove_filter( $hook_name, array( $main_instance, $callback[1] ), $priority );
				}
			}
		}
	}
}