WordPress failure when logging out

I have came across the WordPress logout error several times but I really never figured out the cause of it. In earlier days, it was generally that I was missing a nonce but now even with logout link generated by wp_logout_url();, I am greeted with the WP die screen:

Can serialized arrays in DB be matched against serialized arrays with meta_query?

Say I have an array of checkbox choices associated with a post (a custom field) stored in the database in serialized form. On my site, I present users with the same checkboxes and let them make their choices to “filter” out posts according to their choices. If as little as one of their choices matches a posts choices, that post should be displayed.