According to the ODC Team not all errors returned by the ODC CLI Tool are fatal. Only critical errors should result in a failed build.

The ODC made some changes in ODC 8.0.2 that lead to changed behavior on certain errors. According to the ODC Team the following rules apply:

- exit code 0 signals success with no vulnerable dependencies detected
- exit code 15 indicates a successful run with one or more vulnerable dependencies detected
- exit code 14 indicates non-fatal errors occurred during analysis

- other (1 through 13) indicate various errors that I think are all to be considered fatal errors. 

Here is a link to the report i opened with a detailed description and discussion: https://github.com/jeremylong/DependencyCheck/issues/5616