Replace the milk with a higher fat content one. Or half yoghurt/half greek yoghurt. Add roast, chopped almonds to the cereal.
Replace the cakes with cheeses, salamis, almonds.
Have him have a supplement shake with the noodles. Skip the noodles and make him a sandwich on burgen bread, with mayo, full fat cheese, ham, bit of cucumber, green pepper, tomato.
Add some gravy to the pork chop. Fry it in plenty butter/olive oil. Make dishes with cream in them. Make omelettes with bacon/sausage, bit of cream, fried - add shrooms, spinach, brocolli florets... Make stews with cream in them, serve with cauliflower rice. Make a mousakka on courgettes instead of potatos - plenty cheese etc.
Nudge him to have a bit of food before bed if you can - a bite of cheese, a couple thin slices of ham, some almonds.
Do you know if his sugars are generally okay? Excessive weight loss can be a sign that things aren't quite as they should be in which case he should look at other treatment options - the body needs energy from somewhere and if it cannot use the food properly, it will deplete muscle and fat stores and that is not healthy at all and can be dangerous. It all depends if his sugars are okay, really.
Good luck.