If you can get four or five different whole grains you could cook then until they are soft on the outside and still hard inside and give Sammy some of them after they cool down to room temperature in addition to his fruits and vegetables, a couple of nuts per day would help too if he will eat them.
I am sorry, I didn't think that you had enough posts, that was my mistake and I do apologise for that. I know that you are doing the best that you can and that Sammy has not been with you for more than just a few days. I was concerned about his feather condition and was thinking that it was probably due to having been fed a poor diet by his owner and not by you. This is an awkward situation to work with since you are just babysitting him and only for a couple of weeks. Here is what I feed my birds. I feed a cooked mixture of whole grains ( four to five different ones, depending on what I can get) this is about 40 % then I add blanched vegetables which is normally carrots, green peas, yellow corn, green beans and broccoli, it is also about 40% of the total amount of this food then the last 20% is fully cooked white beans, and lentils. I also give a fresh raw fruit, vegetable and a leafy green. these are for breakfast and for all day eating. then for dinner I give a seed mix and one or two tree nuts ,such as almonds or pistachios, or walnuts. this gives the birds a good variety of natural vitamins and minerals as well as enough fats and protein to utilize the vitamins and minerals as well as enough for the body to repair itself as it should. All food is served at room temperature or slightly cooler.
I wonder about his cage at home, if it is a powder coated cage ( painted ) is the paint chipped or does the cage have any rusty spots that a bird could chew on. If id does have rust spots or bare metal then heavy metal poisoning could be the cause of Juliet's passing. Heavy metal poisoning also attacks the liver and does so at a much faster rate than liver disease from an all seed diet. I also would consider cutting back on the kale as it is very high in iron the same with spinach and it may contribute to him having too much iron and that can be as bad as not enough.
To be honest my very first thought was poor diet, but I would also look at his home cage because heavy metal poisoning is also a possibility. That is the extent of what I have been thinking. I wish that there were more that I could do other than to make these suggestions. I also wish that I knew far more than I do about these wonderful birds. And I wish that I knew how to help you to convince Sammy's owner to give him a better diet.





