Doesn’t work with shortcodes from other classes

This plugin has a feature to allow or disallow users to add shortcodes in the comment form.

However, in the list of shortcodes to allow / disallow, this plugin is missing some (thus, effectively not allowing them to be used in the comment form.)

For example, in my plug-in I have

<?php
namespace myplugin
class myclass {
public function go() {
	add_shortcode ('something_cool', array ($this, 'display_something_cool'));
	add_action ('get_comment_text', array ($this, 'comment_text'));
}
public function comment_text($text) {
	return do_shortcode($text);
}
public function display_something_cool() {
	// the code from this function works without the TinyMCE Comment plugin
	// but, when I turn on that plugin, it no longer runs.
}
}

I don’t know if the namespace is causing this bug, or the use of the class (i.e., add_shortcode (.... $this, 'function') ).

Is this plugin still being maintained? Does someone know how to fix this issue? (Perhaps, if the plug-in no longer being maintained, I’ll be less worried about updating its code myself.)