I am not sure if there is a way to customize the Report Definition click events as such. By default the behavior is to open the instance that you have clicked (on list reports anyway). You can use custom sections to display the data so perhaps something could be implemented in there (I would need to try)?
If you want to perform complex actions then the best bet would probably be to use the Report Definition as the source for a grid, and then use the grid row actions configuration.
Thanks for the explanation. My primedirective, in Pega or any other software, is where you make a decision for the user, document it, and, in general, allow the user to override it safely. This would be one of those situations!
IN RD you can't give custom actions on a row click. If the report is defined on any of Rule- or Assign- or Work- classes then on single click it will open the work object(this is internally decided). For all other classes single click doesn't invoke anything.