Pilots will normally advise ATC of RA immediately. That is the job of PNF. In the DHL accident from recollection, one of the pilots were out of the seat (had just gone to the toilet), so the SOP of PF performing the manoeuvre and PNF advising ATC of RA was flawed. The PF did what he was trained to do but there was nobody in the other seat to report the RA. It is a damning indictment of the aviation training setup. We practice standard "abnormals & emergencies" but never seem to think outside of the box.