Hi there,
Kindly change the code to the one below which adds the post title to the same place for single posts:
add_shortcode('awesome_landmark','awesome_landmark');
function awesome_landmark ( $atts ) {
	ob_start();
	$disable_page_title = get_post_meta( get_the_ID(), '_x_entry_disable_page_title', true );
	$disable_filters    = get_post_meta( get_the_ID(), '_x_portfolio_disable_filtering', true );
	?>
	<?php if ( is_home() && x_get_option( 'x_integrity_blog_header_enable' ) == '1' ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo x_get_option( 'x_integrity_blog_title' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php echo x_get_option( 'x_integrity_blog_subtitle' ); ?></span></p>
		</header>
	<?php elseif ( is_single() ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo get_the_title(); ?></span></h1>
		</header>
	<?php elseif ( is_search() ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php _e( 'Search Results', '__x__' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php _e( "Below you'll see everything we could locate for your search of ", '__x__' ); echo '<strong>“'; the_search_query(); echo '”</strong>'; ?></span></p>
		</header>
	<?php elseif ( is_category() || x_is_portfolio_category() ) : ?>
		<?php
		$meta     = x_get_taxonomy_meta();
		$title    = ( $meta['archive-title']    != '' ) ? $meta['archive-title']    : __( 'Category Archive', '__x__' );
		$subtitle = ( $meta['archive-subtitle'] != '' ) ? $meta['archive-subtitle'] : __( "Below you'll find a list of all posts that have been categorized as ", '__x__' ) . '<strong>“' . single_cat_title( '', false ) . '”</strong>';
		?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo $title ?></span></h1>
			<p class="p-landmark-sub"><span><?php echo $subtitle ?></span></p>
		</header>
	<?php elseif ( x_is_product_category() ) : ?>
		<?php
		$meta     = x_get_taxonomy_meta();
		$title    = ( $meta['archive-title']    != '' ) ? $meta['archive-title']    : __( 'Category Archive', '__x__' );
		$subtitle = ( $meta['archive-subtitle'] != '' ) ? $meta['archive-subtitle'] : __( "Below you'll find a list of all items that have been categorized as ", '__x__' ) . '<strong>“' . single_cat_title( '', false ) . '”</strong>';
		?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo $title ?></span></h1>
			<p class="p-landmark-sub"><span><?php echo $subtitle ?></span></p>
		</header>
	<?php elseif ( is_tag() || x_is_portfolio_tag() ) : ?>
		<?php
		$meta     = x_get_taxonomy_meta();
		$title    = ( $meta['archive-title']    != '' ) ? $meta['archive-title']    : __( 'Tag Archive', '__x__' );
		$subtitle = ( $meta['archive-subtitle'] != '' ) ? $meta['archive-subtitle'] : __( "Below you'll find a list of all posts that have been tagged as ", '__x__' ) . '<strong>“' . single_tag_title( '', false ) . '”</strong>';
		?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo $title; ?></span></h1>
			<p class="p-landmark-sub"><span><?php echo $subtitle; ?></span></p>
		</header>
	<?php elseif ( x_is_product_tag() ) : ?>
		<?php
		$meta     = x_get_taxonomy_meta();
		$title    = ( $meta['archive-title']    != '' ) ? $meta['archive-title']    : __( 'Tag Archive', '__x__' );
		$subtitle = ( $meta['archive-subtitle'] != '' ) ? $meta['archive-subtitle'] : __( "Below you'll find a list of all items that have been tagged as ", '__x__' ) . '<strong>“' . single_tag_title( '', false ) . '”</strong>';
		?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo $title; ?></span></h1>
			<p class="p-landmark-sub"><span><?php echo $subtitle; ?></span></p>
		</header>
	<?php elseif ( is_404() ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php _e( 'Oops!', '__x__' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php _e( "You blew up the Internet. ", '__x__' ); ?></span></p>
		</header>
	<?php elseif ( is_year() ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php _e( 'Post Archive by Year', '__x__' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php _e( "Below you'll find a list of all posts from ", '__x__' ); echo '<strong>'; echo get_the_date( 'Y' ); echo '</strong>'; ?></span></p>
		</header>
	<?php elseif ( is_month() ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php _e( 'Post Archive by Month', '__x__' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php _e( "Below you'll find a list of all posts from ", '__x__' ); echo '<strong>'; echo get_the_date( 'F, Y' ); echo '</strong>'; ?></span></p>
		</header>
	<?php elseif ( is_day() ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php _e( 'Post Archive by Day', '__x__' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php _e( "Below you'll find a list of all posts from ", '__x__' ); echo '<strong>'; echo get_the_date( 'F j, Y' ); echo '</strong>'; ?></span></p>
		</header>
	<?php elseif ( x_is_portfolio() ) : ?>
		<?php if ( $disable_page_title != 'on' || $disable_filters != 'on' ) : ?>
			<header class="x-header-landmark x-container max width">
				<?php if ( $disable_page_title != 'on' ) : ?>
					<h1 class="h-landmark"><span><?php the_title(); ?></span></h1>
				<?php endif; ?>
				<?php x_portfolio_filters(); ?>
			</header>
		<?php endif; ?>
	<?php elseif ( x_is_shop() && x_get_option( 'x_integrity_shop_header_enable' ) == '1' ) : ?>
		<header class="x-header-landmark x-container max width">
			<h1 class="h-landmark"><span><?php echo x_get_option( 'x_integrity_shop_title' ); ?></span></h1>
			<p class="p-landmark-sub"><span><?php echo x_get_option( 'x_integrity_shop_subtitle' ); ?></span></p>
		</header>
	<?php elseif ( x_is_buddypress() ) : ?>
		<?php if ( x_buddypress_is_component_with_landmark_header() ) : ?>
			<header class="x-header-landmark x-container max width">
				<h1 class="h-landmark"><span><?php echo x_buddypress_get_the_title(); ?></span></h1>
				<p class="p-landmark-sub"><span><?php echo x_buddypress_get_the_subtitle(); ?></span></p>
			</header>
		<?php endif; ?>
	<?php endif;
	return ob_get_clean();
}
Regarding the centering, you can add the shortcode to the Text Element and use the Text Element options to set thing correctly.
kindly get back to us with the URL/User/Pass of your WordPress dashboard using the Secure Note functionality of the post to follow up the case.
Thank you.