Import demo data from theme and plugin

Hi, great theme thanks!

I have a theme that provides a bunch of demos perfectly.
I’m working on a plugin that offers a themed set of demos to add to the list of available demos.

I cant get my plugin demos to append to the list of available demos.

Theme code:

function wpcake_import_files() {
	return array(
	    array(
	      'import_file_name'             => __('Restaurant', 'wpcake'),
	      'categories'                   => array( __('Food', 'wpcake'), __('Business', 'wpcake') ),
				'import_file_url'            		=> 'https://www.wpcakedemos.com/demo_data/restaurant/content.xml',
	      'import_widget_file_url'     		=> 'https://www.wpcakedemos.com/demo_data/restaurant/widgets.wie',
	      'import_customizer_file_url' 		=> 'https://www.wpcakedemos.com/demo_data/restaurant/customizer.dat',
				'import_preview_image_url'   		=> 'https://www.wpcakedemos.com/demo_data/restaurant/screenshot.png',
	      'preview_url'     							=> 'https://www.wpcakedemos.com/restaurant/',
	    ),...
 );
}
add_filter( 'pt-ocdi/import_files', 'wpcake_import_files' );

Plugin code:

function wpcake_extra_import_files() {
	$demos = array(
	    array(
	      'import_file_name'             => __('Bubble Cake', 'wpcake-extra'),
	      'categories'                   => array( __('Cake', 'wpcake-extra'), __('Startup', 'wpcake-extra') ),
				'import_file_url'            		=> 'https://www.wpcakedemos.com/demo_data/restaurant/content.xml',
	      'import_widget_file_url'     		=> 'https://www.wpcakedemos.com/demo_data/restaurant/widgets.wie',
	      'import_customizer_file_url' 		=> 'https://www.wpcakedemos.com/demo_data/restaurant/customizer.dat',
				'import_preview_image_url'   		=> 'https://www.wpcakedemos.com/demo_data/restaurant/screenshot.png',
	      'preview_url'     							=> 'https://www.wpcakedemos.com/restaurant/',
	    ),...
);
}
  add_filter( 'pt-ocdi/import_files', 'wpcake_extra_import_files' );

Will pt-ocdi/import_files run twice?
Do I have to setup demos differently in plugins?

Thanks
S