How to display user picture programmatically in a rule (User Relationships)
Try something like this, just for grins. Make sure you're actually returning the URI, and maybe provide an alternative image if they don't have one for themselves. Also, your link might be messed up.

I'm not entirely sure how you're getting that URI for the profile image.

$imgpath = $requestee-&gt;picture[und][0]['uid']-&gt;uri; // Maybe? I would think the URI is in the picture array.
$vars = array(
  'style_name' =&gt; 'thumbnail',
  'path' =&gt; $imgpath,
  'attributes' =&gt; array(
    'class' =&gt; array('RequesteesPicture'),
  ),
);
$image = theme_image_style($vars);
$link = l($image, "user/" . $requestee-&gt;uid, array('html' =&gt; TRUE));
print $link;