Thanks Uri for the catch, then when id_user_guest is NULL it won't be considered a duplicate.

models/intermediate/core/int_core__bookings.sql

@@ -26,7 +26,7 @@ select
     b.id_verification_request,
     vrbs.verification_request_booking_source,
     b.id_staging_host_booking,
-    db.is_duplicate_booking,
+    coalesce(db.is_duplicate_booking, false) as is_duplicate_booking,
     db.is_duplicating_booking_with_id,
     bs.booking_state,
     b.check_in_at_utc,

models/intermediate/core/int_core__duplicate_bookings.sql

@@ -12,6 +12,7 @@ with
                         order by id_booking asc
                     )
                     > 1
+                    and id_user_guest is not null
                 then true
                 else false
             end as is_duplicate_booking,