Excuse me for such a delay with answer.

My test shows that ‘All’ posts list is empty for user with ‘ECD Curator’ role just in one case when there special constant for WP Engine is not defined:
define(‘WPE_GOVERNOR’, false);

You have it in a provided files copy. I just suppose that you met a problem with another (possibly stage) copy, do you?

I will continue with numbers count tests.