My problem is this:
When in Development environment, everything is OK - the poller is working fine, the DB statuses changes, etc.
So I got this running now. It was a security problem. When you run the application on your local workstation on worklight studio and liberty profile, some security features are disabled which is not the case of the production.
On development mode all the procedures with no explicit securityTest have wl_inprotected by default I think they did it like this in order to be able to invoke procedures from Eclipse. In the production environment the security is enhanced and wl_unprotected is not considered as the default security test.
So what I did is to add securityTest="wl_unprotected" for all the procedures in the execution chain except the sendNotifications procedure which should remain without sec test.
That's it !