// Get the initial batch of events (includes multiple instances of recurring events).
$args = array(
  'post_type' => 'tribe_events',
  'post_status' => 'publish',
  'posts_per_page' => 30, // Can be anything, we just need enough to still have at least 3 when recurring events are filtered out.
  'meta_key' => '_eventstartdate',
  'orderby' => 'meta_value_datetime',
  'order' => 'ASC',
  'meta_value' => date("Y-m-d H:i:s"),
  'meta_compare' => '>',
  'tag' => 'featured-event-home',
);
$the_query = new WP_Query( $args );
$posts = $the_query->posts;

// Pull post ID and title from the results above. That's all we need to find "duplicate" events.
foreach ($posts as $post) {
  $simplified_postdata[$post->ID] = $post->post_title;
}

// Duplicate the simplified postdata into an array we will filter.
$filtered_postdata = $simplified_postdata;

// Loop through the postdata array to remove duplicate events (matching titles). Events are only removed from the filtered array.
foreach ($simplified_postdata as $inspected_id=>$inspected_title) {
  foreach ($simplified_postdata as $comparing_id=>$comparing_title) {
    if ($inspected_title === $comparing_title && $inspected_id < $comparing_id) {
      unset($filtered_postdata[$comparing_id]);
    }
  }
}

// Create an array of post IDs from the filtered postdata array.
$ids = array_keys($filtered_postdata);

// The final query args.
$args2 = [
  'post_type' => 'tribe_events',
  'post__in' => $ids,
  'posts_per_page' => 3,
];

// Do another query and loop through the results to display them.