Hover images and Videos

At first blush, it appears that you are missing a colon from your else statement. Without more info, though, I cannot tell you anything else.

<?php if( has_post_thumbnail() ) : ?>

    <div class="image-wrapper-hover">
        <?php the_post_thumbnail( 'large' ); ?>
    </div>

<?php else : ?>

    <?php catch_video();?>

<?php endif; ?>