Thank you for the advice everyone.
Unfortunately as a single income family I cannot really afford to see sport physiologists or other such specialists
I did end up going to Mt Maroon on Saturday after the 6 week hiatus. I found it considerably more difficult than usual, I seem to have lost a lot of my stamina and needed to rest frequently. I also experienced knee soreness on the way down, and today (the next day) so I guess I am not done healing yet. It did not help that the temperature soared up well above 30 degrees Celsius. I experienced jelly legs on approx 1/3 of the way down which I have not experienced in a long time.
On the drive out on Cotswold Rd I experienced a frightening episode where half way down the road, my right leg (not the injured one) became severely cramped, and I had to pull the car over (braking with my left foot) in the middle of the dirt road, and lie down on the ground outside trying to straighten my leg for two minutes. I had been drinking electrolyte throughout the walk, and in the car so I am at a loss to explain it. It did not happen during the walk.
But I did make it. I think a big part of it is that once you get the mental fortitude, you do not lose that ever. You know you can make it. It is just a question of time, additional effort and extra fatigue.
I have incidentally been using a single walking pole ever since May in most hikes. Results are mixed. Some walks I returned from and experienced little knee issues. Some I had dramatic knee issues afterwards. Whether or not I had a pole did not seem to be a factor, neither the difficulty (steepness, looseness, scrambling level, elevation etc). I was perplexed by this when I was doing this before my MRI. The pole should reduce load on the knee. Maybe I was using it incorrectly or something. The length, stability of the terrain and gradient should factor also. I had simple walks I returned from with a pole and suffered dramatically the next day. I had long and difficult walks (Barney SE Ridge) with no pole I returned from with little impact the next day.
Fortunately as we go into the warmer months the walks tend to turn to flatter rainforest walks, and not mountains so the effort and impact should reduce drastically.
I have a plan for practice walks also. I catch the train to and from work into Brisbane City. I live in Logan Central. I can get off a station earlier most workdays on the way home and walk 6km through Karawatha Forest which is flat on the way home. I can also get off two stations early one day a week and walk through Kuraby Bushlands and Karawatha forest which is nearly 10km. I have done both before, but haven't been doing that lately.