Hi John, after thinking through the information you provided, I was in fact able to come up with an easy solution:
$office_employees = get_users( array(
'meta_key' => 'office_name',
'meta_value' => 'Office 1',
'fields' => 'ID'
));
$office_listings = get_posts(array(
'author__in' => $office_employees,
'posts_per_page' => -1
));
if( $office_listings ):
endif;
Thanks!