Dear Pedro,
the audit log says that provisioning did not take place and hence the Firefighter has not been assigned. Provisioning log, as mentioned by Plaban, is empty (as stated in the audit log).
I suggest to check SLG1 application log for user WF-BATCH with the time of provisoning. Check if there is an error message or share with us.
Also I recommend to activate escape handling for "Auto Provisioning Failure" in case an error occurs.
Hope this helps.
Regards,
Alessandro