OK, now that you have clarified your situation, I am going to give some advice, hope you take it on board and then I am going to disengage (as if you are trolling, I believe trolls should be left to live in the wild, and so I try not to feed trolls

). Assuming you are not trolling:
This eclectus may have passed away in a nest with it's mother doing it's best, or it may have gone on to live in the wild for a very long time, we will never know what would have happened, sadly we only know what did happen. The person who captured this bird (as you say) was simply looking to feed his family, and I can't blame him for that. If this is the case he is clearly going to be unprepared to have what is needed to give this young eclectus the essential basics for survival at such a young age, even you admit to not having the necessary equipment to look after this bird. Based on your description of how this bird was in the first week, and the lack of treatment and care you were able to provide, he would have had a far better chance of survival in the wild. You said yourself others you have raised were 9-10 weeks old and this one was much younger, even 9-10 weeks if far too young to raise with your lack of equipment and experience. So I am sorry to say that the capture and captivity may not have been the cause of death, but was probably the underlying cause of death.
By purchasing these birds, you are encouraging this person to pursue wild bird capture as a possible source of income, and at best he will stick to birds that are not endangered, but as he learns his trade and sees the profits to be made in the capture of endangered species such as the Birds of Paradise, who could honestly blame a man who is trying to feed his family and as you say "lives in extreme poverty". If you are in a position to help, and want to offer support, buying birds off them is not the right way to do it, at best you are encouraging them to move away from other possible ways to make a living, at worst you are driving them into the illegal trade sector.
I've been doing this for 8 years and have only ever lost 1 eclectus and a goshawk.
And I've only ever lost two birds a barn owl and goshawk and they had a terrible case of aspergillosis when I trapped them and they died the next week.
and the goshawk was one we pulled out of a power line.
It's 3 now isn't it, not 2, or is it 4? As you can see, you also mentioned loosing a Barn Owl (which would make 3), but was the Goshawk that you pulled out of a power line the same one that you trapped, or have 2 Goshawks passed away.....I'm a bit confused?? Perhaps your trap is made of power lines

.
I've only ever trapped two eclectus parrots from the wild but that was for a banding project. The ones I trap are birds of prey I trap a juvenile bird train it hunt with it for a season and let it go before the breeding season. And after the breeding season I trap another. And this is known to increase the population because I teaches juvenile birds to hunt better. The mortality rate of juvenile birds of prey in the wild is 70% die in there first year.
If you have only ever trapped two eclectus, then based on your previous statements you have bought a few, capture or bought, it doesn't matter.
Your approach is not helping these birds overall chance of survival. The advantage a 2 year old bird of prey has over a 1 year old is life experience. Yes the first year is a hard road for these birds and mortality is high, but the reason the mortality rate drops in the second year is not something you are going to be able to achieve with captivity. I don't think it matters how good a trainer you are, you just can't match this year of experience they are missing out on in the wild, so please don't kid yourself with this 70% mortality statistic.
Most agree that within 4 weeks a bird of pray will loose almost 70% of it's fitness in captivity, as these birds do not have much of a down time in the wild, it's hunt, miss, hunt, miss.....hunt capture..... You simply can not simulate this environment in a year of captivity. Sure you can increase it's fitness before release, but you have stunted it's development, and now you are releasing it into the wild when it has spent most of it's life in captivity. This is not even taking into account the risk of mortality associated with capture, and captivity.
The reality is you can't know how many of these birds that you have captured or bought and then later released have later passed away due to their inability to now survive in the wild (a successful release of a bird of pray means you are unlikely to ever see that bird again). Captivity of a wild animal for later release is a last resort approach, and you have no reason for what you are doing. If the bird of pray you trap was one of the lucky ones that would have made it through the year in the wild, then you have drastically dropped it's survival chances for the coming year.
My suggestion would be if you truly want to have a relationship with native birds in Papua New Guinea, get involved in conservation and education. You are in a perfect place for this, were the country has over 5% of the world's biodiversity in less than 1% of the world's total land area.
Edit: I was writing my post when you were writing post #26. Your post #26 does not change my opinion in what I have written. I am just updating to clarify, as your context has changed a lot in post #26.
I don't want to be rude or anything but I do know what I'm doing.
I am sorry, but you do not, at least in as far as raising eclectus parrots. I am no expert on eclectus parrots, but your approach shows your ignorance even to me. As for birds of pray, I don't see the Sydney Zoo recommending the removal of a native bird from the wild, keeping it in captivity for a year and then releasing it.