Certainly, reading the information CASA has released to you under FOI on the incident a few years ago, where reports of staff being threatened, buildings locked down, staff having to work from home, avoid wearing identifying uniforms, security beefed up in Canberra, Melbourne and Moorabbin, it would appear that taking the law into your own hands is not the most effective way to resolve this issue. Reading this from a non-biased view (embarrassed and having no axe to grind for anybody involved), it would appear that CASA had valid concerns (in their own eyes - which is what matters), that you were stalking and threatening. I am astonished this was not brought up on these forums in discussion before - it certainly helps explain why CASA has been avoiding you (and the direction to staff to not engage you in public, or specifically in these forums that have been mentioned by name). Your future discussions should be in a courtroom, in front of a judge, and possibly a jury, and let the lawyers present your case in a factual, effective, emotionless way.
Looking back, if you had attended with a lawyer (or preferably sent them instead to speak with a level headed legal approach) to serve notice of intended legal proceedings, and had actually followed through with it, these matters may have come to a favourable conclusion many years ago.
All is not lost. I can understand the reticence of CASA to have any further face-to-face meeting with you, and your heightened emotions taking a leading role in your approach to dealings with CASA at the time, you will probably find a couple of beefy Federal Police in attendance at your appointment in a few months in Canberra to make sure matters do not become heated. Carefully consider your current frame of mind - is there even a slight possibility it might become emotional - if so do not go alone. Wouldn't a well briefed lawyer that was engaged all those years ago have been a more favourable approach? You certainly will do a lot to relieve their anxiety if you would attend with a well briefed lawyer from now on if you insist on making this personal in the future. Are you still hell-bent on taking down the individual public servants, or has your attitude changed to now understand that the organisation is ultimately responsible for the delegated actions of their officers, and responsibility goes up the line right to the top? Who will you sue - the individual or the organisation? Who will pay you the millions you deserve to right this matter on just terms? Would a begrudging forced written apology from the offending individuals right the situation and reverse your fortunes?
An apology for the threatening and inappropriate way you carried on all those years ago may help calm things down. Whether you should do this before, during, or after your court case is something your legal counsel will advise you on.
Airing your grievances in these public forums and trying to do everything in an amateurish way has possibly cost you the most favourable outcome. Yes, it would appear you have quite a valid case, and the threats you made are just but a small diversion, but can I continue to strongly suggest you place this matter in the hands of a competent lawyer and let them run with it instead of playing amateur lawyer? You have been trying to justify your approach in these public forums. It has obviously not worked, as it is the wrong approach. Talk to your wife and family and friends and ask their opinion and then listen to it. Go get a lawyer and take it from there.