The debug option for the CLI is listed as a global option but it doesn't seem to work for save-parser. I was assuming if you created the parser with the -d option that it would apply when you used that parser to parse. If this is incorrect maybe there should be more specific wording in the help and the Command Line Interface page on Confluence. Also CLI requirements would need to be updated.
See test - test_3036_CLI_Saving_SaveParser_debug in daffodil-cli/src/test/scala-cli/edu/illinois/ncsa/daffodil/saving/TestCLISaveParser.scala