shit, 4 is pretty young, my dude was diagnosed at 10 w/ lip cancer, removed part of his lip and he looked like mean one sided dog but he was recovering for 6months really well.
his whole life i just had him on iams, never human food and vet said he was super healthy (from the vet scale of 1-5, one being dead skeleton and 5 being an overweight shit, he was always a 3). after he had his surgery they told me to cook some rice and veggies and meat for him, since dog food might be too hard for him to eat.
fuck, he looked healthier than hes ever been after a month of just straight eating human cooked food.
it was really simple too, 3 equal portions of
rice
veggies
meat
i'd cook about 3 or 4 cups ahead of time, i'm super asian, so i know my rice, short grain or jap/korean rice can be kept cooked in the fridge and it won't harden, even walmart sells my fav brand
5 bucks for a 5pound bag, buy a
cheap panasonic rice cooker you don't need a bomb ass expensive zojirushi rice cooker, of course obviously i have one, cuz i'm asian, but i use the small panasonic more b/c i'm not cooking for like 20 immigrants.
just wash 3 cups in a collander, pour it into the rice cooker drained and fill it up with water until it covers the rice w/ 1/4in of water. (asian pros like myself either eyeball it, or use the stick a finger in the rice test)
for veggies just get straight frozen mixed veggies, thats it, i mean they're washed and cut and flashed frozen to keep the nutrients.
then just cook the meat
for chicken, i roasted it using
beer can either get a holder, or really just stick a chicken on a beer can in the oven. you don't have to use beer, you don't even have to use anything but just water, 90minutes it'll come out amazing. you only wanna put seasonings and aromatics for humans, but dogs don't need that shit, they just want yummy cooked food.
i never like store bought ground meat, so i just cooked up either chuck steak or center cut pork chops, the leaner cuts of meat.
you can do this too, it's really simple, if you believe you can give your dude a few more weeks, then try to give him a more balanced diet instead of just straight meat, he might be more peppy. and have more energy to finish that bucket list.
and yea absolutely no seasonings or anything, dogs don't need it, and if you don't want to grill your outside, pan frying is really simple.
get a nice stainless steel pan or cast iron, put it on high and put 1tbsp butter/1tbsp canola oil (basically half/half) (don't use olive oil, it has a low smoke point), only when the oil slightly smokes, put the meat on (still high), for 3mins, flip it around, cover and turn off heat, ready in 6 mins.
honestly roasting chicken was the more economical way, if however you find breaking down a chicken (removing all the meat) is a bit difficult, then try pan frying.