My name is ***** ***** I am a NSW Solicitor. Thank you for your question, and will do my best to assist you with your question. Please understand this is not legal advise Please understand this is not legal advise but a guide to assist you.
If the mother in law had knowledge of what they were doing then yes she can be implicated as an accessory.
The main person will go to jail the other 2 may not go to jail but will get a fine and have a record.
If they were sharing in the money the they may also go to jail it all depends on their role in the fraud.
If you are anonymous then they cannot find out. It you are to be a witness to prosecute them then they will know it is you as you will have to give a statement and you will be a witness for the department if they plead not guilty.
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