WP_Query with meta_query no results

Your code looks correct. Have you checked your stored meta data to confirm the value stored is 1? Also, have you tried comparing to a string value, eg ‘1’ instead of 1? Just a stab in the dark, but worth a shot.

Assuming your stored values are correct, and seeing as the values can only ever be 1, you could try using:-

'compare' => 'LIKE'

LIKE usually works as a partial match, but in your case, it shouldn’t make any difference.