This is a 7.4.1 system with no legacy reports available. If it had been 7.5+ and BSARA, may be a custom report would have given me the information.
DATE_MODIFIED is only changed when you save the template.
You probably need to dump all the jobs that could use a template (compliance, audit), get the date of their last run, and get the template associated w/ the job. I think you can get the dependent jobs from the template objects, and then find the latest runs from the jobs...