According to the Codex, you seem to skip the most important global $post;
at the beginning, like this:
global $post;
$posts = get_posts($args);
foreach($posts as $post) {
setup_postdata($post);
?>
<article class="col two tablet-four mobile-six box">
<a href="https://wordpress.stackexchange.com/questions/131909/<?php the_permalink(); ?>" title="<?php the_title_attribute(); ?>">
<div class="featured-image">
<?php if(has_post_thumbnail(get_the_ID())): ?>
<?php $image = wp_get_attachment_image_src(get_post_thumbnail_id(get_the_ID()), array(650,200)); ?>
<div style="background: url('<?php echo $image[0]; ?>') center center no-repeat;"></div>
<?php endif; ?>
</div>
<section class="content">
<?php $cat = get_the_category(get_the_ID()); ?>
<span class="category"><?php echo $cat[0]->cat_name; ?></span>
<?php the_title(); ?>
<?php the_excerpt(); ?>
</section>
</a>
</article>
<? }
wp_reset_postdata();