First off sorry to hear about your accident. Are you reimbursed for food you purchase? Carbs and protein are kind of hard to make on the road assuming you don't have access to a stove..
Here are some tips:
Drink cold water throughout the day. Start with 1 gallon but with so much traveling you might bump it up if you are still dehydrated. You burn a little more calories drinking cold water than room temp. Yes there is a thing as too much water: water intoxication, hypokalemia (low potassium), and hyponatremia (low sodium).
Eat vegetables at least 3 times per day. Low calories but full of nutrients and fiber.
Fruits: Start your breakfast off with fruits and sprinkle throughout the day. Avoid eating at your last few meals of the day.
Not sure yet exactly what I can advise when you are traveling. If you could have access to a stove 2 days per week that would be sufficient to cook your carbs and protein for the week.
Do not consume list:
Pop, alcohol, processed foods, foods loaded with sodium, foods laced with hydrogenated oils or high in saturated fat.
Stick to complex carbs and 6-8 meals per day.
1500 calories is too low for a 320lb man. Do a 3 day journal of what you are currently eating, take an average of the macros and this is your baseline. From here reduce by 1000 calories. Take your measurements right now (bf, bodypart measurements, bodyweight), take pictures so you can compare as you make progress and track your progress.
Some good foods for traveling that come to mind: nuts (preferably unsalted almonds), fruits, vegetables, skim milk, whey protein.
You might try buying a coffee grinder and grinding up your complex carbs to make a shake. Grind up brown rice or oatmeal, you could even throw in some
flax oil or olive oil, fruits, whey protein and this would keep you going and be really easy.
Please let me know if you have any other questions. You might be better served to pm me if you do.
Hope this helps. Good luck on your recovery and attaining your goals.