fincher on "Bilingual Welcome Page on the front page above the index"

Hello! I use Polylang plugin and it's all fine, except that I can't switch between my two Welcome Pages to display on the front page of the website above the index. I've made two separate .php files to recall each welcome page by its title. But I don't know how to address these two files separate in index.php, so that when first language is selected in the menu, the first front page is displayed and vice versa. So far I'm able to display only one chosen Welcome Page, regardless switching between languages. I use this code on the top of index.php:
<?php
if ( is_front_page() && !is_paged() ) :
get_template_part( 'welcome' );
endif;
?>
Any ideas?