I also had a similar backup and restore issue and I also implement this command which you are sharing here, but it doesn't work for me can you please share something else which help me to solve my issue.
Sorry Sammyadam for the late response,
the path of course is your preference. drive:\path\filename.zip but you probably done that and I was talking about a scheduled task on Radioboss. Can you give more explanations on what was was your issue ?