Gallery with shortcode not showing

While gallery shortcode does have id arguments, it won’t do what you think.

If that argument is present WP will try to look for child attachments of that post, using get_children(). It won’t take content of the post and shortcodes in it into account.

If the gallery is only content of that page you could try the following (not tested):

echo do_shortcode( get_post_field( 'post_content', 63 ) );