Okay, I just went ahead and tested this in my test environment, and i was able to delete the job.
What I've done:
- Removed all the relations between the candidate and the job via the CDS;
- Deleted the Job directly from Attract;
As a result.. all my history and data is actually deleted and can't be found anymore (but I assume that's your goal):
Log in to the CDS: and open the data entities where you want to delete the data from:

Select the line you need to be removed, delete from excell and click Publish:

This will result in deleting data:

Applicants will be removed from the applicant list in Attract:

Final step is to remove the applicant from this list (data entity = Job Application Status):

Once that's done, you can remove the job:
