the_content_rss not echoing anything

One of the plugins that I am using (featured-content-gallery) uses the function the_content_rss to extract some of the text from each post. The function is being used inside The Loop, however, it does not seem to be returning any content.

Below is the code that the plugin is using:

<?php if (have_posts()) : while (have_posts()) : the_post(); ?>
       <div class="imageElement">
            <h2><?php the_title() ?></h2>
            <?php
                 if(get_option('gallery-use-featured-content')) {?>
                 <p><?php $key="featuredtext"; echo get_post_meta($post->ID, $key, true); ?></p>
                 <?php
                 } else {
                 ?>
                 <p><?php the_content_rss('', false, '', $wordquantity); ?></p>
                 <?php
                 }
?>

Could anyone help me figure out why the function would not be returning any text? Thanks