I found this information about Lilly Pilly at Burkes Garden Site: Lilly Pilly Fruit: Lilly pillies are handsome rainforest trees native to Australia and south-east Asia. They've become tremendously popular in Australian gardens, particularly for hedging and topiary. As well as having evergreen, glossy leaves and masses of fluffy white flowers in late spring to summer, they also produce colourful, edible berries. The purple fruit of Syzygium australe. This lilly pilly is about the size of a small marble, but fruit size does vary from one species to another. Although lilly pilly fruit is edible, it is not very tasty. However, it is delicious made into a chutney, or try the recipe below for lilly pilly jelly.

Is it a Syzygium or a Eugenia - and what sort? Most of them are 'full sun or part shade' plants so some sunlight each day would be an idea. Start with morning sun - somewhere it won't get too hot because it won't be hardened off at all. Have you got a porch you could put it on? Or under a garden tree that lets dappled light through. You might be overwatering, too. If it is drying out really quickly between waterings - it might need repotting - and possibly some root pruning if it has run wild in the pot. If it's OK, then put it up on feet in the protection saucer so the surplus water can drain away and air can get to the roots. Wait until the soil feels dry as deep down as the first joint on your finger - then water thoroughly. If the pot is not too big - put it into a bucket of water and wait for the bubbles to stop - but get it out within ten minutes, and let it drain before putting it back on its feet. And some of it could also be 'changing leaves' for spring. A lot of the evergreens do a leafdrop around now. Another possible is being in a cold draught. Easy-fix, that one!

Possibly scale, check the branches and see if there's a little, hard, bug infestation that's hard to remove, though you can flick them off with your finger nail sometimes. If there is, there's also likely to be ants travelling up and down the tree, they 'milk' the scales for their secretions. 'White' oil is the treatment - it chokes the bug and prevents it from sucking. You should also apply a ring of petroleum jelly around the base of the bush to stop the ants. I sometimes use a commercial insecticide but a lot of gardeners believe that's a no, no, now-a-days on account of possible damage to friendly insects.

Gosh, it seems there's huge ecological restoration needed in your neighbourhood, blckrose. You've certainly described an environmental disaster zone of monumentous proportions. All of those factors you mention have had enormous negative impacts on native wildlife thereby causing many people to reach for the sprays because natural controls are no longer present. As you would be aware, Noisy Miners have proliferated because of the massive clearance of native understorey thereby creating their preferred open woodland conditions. You might also be aware that a number of communities are now conducting Indian Mynah eradication programmes in order to encourage the return of native woodland birds, many species of which are threatened but provide wonderful environmental services such as control of insect pests if given the chance. Cat controls are also slowly gathering pace but, of course, much more is needed if we are to have a cat-free, native wildlife restoration culture in Australia. So if we are to reduce the impact & cost of sprays in our environment then the issue needs to be tackled on a very broad, multi-pronged front, as you are perhaps implying, blckrose.