Hello Steelz,
I am very sorry to hear about your NER and that we could not have a happy ending to your story.
The bad news are that this NER cannot be converted to PER, your consultant failed to provide enough documentation to show your 4 years of experience. The officer worked based on the documents on hand and he awarded the points based on it. Your consultant made the mistake and he should refund or re-work on your case next year.
The good news are that you can re-apply next year and for sure you will get a PER, 3131 will be on the list next year and you will have 5 years of experience to show instead of 4.
Please be aware that they will probably award less points for experience next year and more for age if you are between 30-35 years old and language skills (as far as we know) so prepare youself and make sure your applications reaches Sydney first week of July next year.
Please check ur Inbox as well, I have sent you a PM.