Why do you have a PHP file in your templates directory?!
themes/main/templates/Includes/AlbumList.php
Is that a typo?
If you look at how you have your template set up, you're not in an album control when you're trying to call those field values. Try:
<% control CurrentAlbum %>
<h5>$AlbumTitle<span class="album-info"> by $PostPhotographer</span></h5>
<p class="articleDate"><strong>Venue:</strong> $PostVenue</p>
<% end_control %>