How do I actually get a field value using field_view_value()?
You may have the field_view_value parameters wrong. Instead of the entity_type-> delta try loading the field first using field_get_items. Use the return value as the second parameter in field_get_items. 

$node = node_load($nid);
$field = field_get_items('node', $node, 'field_name');
$output = field_view_value('node', $node, 'field_name', $field[$delta]);


I took that answer from the blog: https://www.computerminds.co.uk/articles/rendering-drupal-7-fields-right-way