TestExecute and Jenkins (Test Result)
If I understand it properly, the Jenkins plugin for TestComplete/TestExecute is that it builds a wrapper around the command-line execution of tests via TestComplete/TestExecute. The command-line only returns certain exit codes based upon the execution. The actual error message, warning, etc., is not included in that return. So, a short answer to your question, as it stands right now, I don't think there is a way to get the actual error message that caused a failure.