This site is opposed to all breeding of parrots for pets
. I am also vehemently opposed to the selling of unweened parrots to pet owners. Hand feeding is a very demanding job, that should not be attempted by the novice person even after a few in-store lessons. If anything goes wrong with the process, it is always the infant bird that pays the price.
The fact that you were able to go for 4 months and your poor bird only had to suffer only one incident of crop damage, is a testament that you did better than average. Many times, a chick will have to endure multiple incidents of crop damage at the hands of a novice.
I got lucky and found a board certified avian veterinarian. Days later surgery fixed my Rocky as good as new.
Rocky was defiantly lucky that you got him the surgery that he needed. Unfortunately, the surgery did not make him as good as new. The crop is a stretchy material that expands and collapses. After the surgery some of material became scare tissue which is less elastic. The incident will effect his eating for many months, if not the rest of his life.
The selling of unweened chicks to a person who in not certified to feed chicks may not be illegal in many US. states, but it should be. I consider it be almost a Bait and switch
, the only deference is that you pay the veterinarian the money to correct the damage done by taking the bird home too soon. The only reason birds are sold so young is that the breeder/store can entice the customer with low prices. If you would have applied he money spent on the vet towards a bird that was "fully capable of self-feeding" these incidents would be avoided. (This site is still apposed to birds from breeders, I just consider it to be less bad)
I am not convinced that the crop damage was caused by the hot pasta incident, it could have been caused by a miss-feeding a few days later. I don't intend on arguing the point, because it is irrelevant what caused the crop damage. It is possible that the hot pasta incident has scarred Rocky away from trying other types of foods, It is really any ones guess at this point.
There are many things that make hand feeding dangerous for an infant bird. One is the temperature thing. The food must be feed at the parent bird's body temperature, just like your body temp it only varies by a Fahrenheit degree or two. A parent bird does not have to think about it, the food will naturally come out at the right temp. Bird's body temp is higher than a human. When a human has to prepare the food, it is very easy to make the food to hot or too cold just by missing the target temperature by 3 to 5 degrees. When a chick is very young, it's body can not produce the heat needed to warm the food. The crop empties into the stomach by reflex action. The chick's reflex action will not allow cold food to enter the stomach. This is why cold food can cause problems such as impacted crop and others. Once the bird is mature enough and "fully capable of self feeding" he/she can consume food at room temperature.
PS. I do not know which species of cockatoo Rocky is, larger species mature at a slower rate than smaller ones.