Ok i think your suggestion should work.
1) This is visual composer: https://ibb.co/JBmv1DH as you can see i have layout grid 8967
2) If i go to edit that section: https://ibb.co/Rpqx5c4 in url i can see /post.php?post=8967&action=edit
3) In inspector i can see the tag layout_8967 as class: https://ibb.co/RT0cg4J
So the code should like this?
if (get_post_type() == 'layout_8967' && get_field('vedi_autore') == 'si') {
Output Post Author element
}