DCORS, D-FSOR and ASIMS
As Bob says, a DCORS is available as a totally confidential means of raising flight safety issues, but the problem with this type of reporting is that it is very difficult to do anything with these reports without a name attached to it to find out more information.
Hopefully, if the right safety culture exists, people would raise a D-FSOR on ASIMS as a Hazard/ Observation and put their name to it so that the Occurrence Manager has someone to come back to for more information.