+1 to the breakfast smoothie!
DH and I are endurance athletes, and looking at your meals/snacks it really sounds like you are skimping on your lunch calories especially (unclear what type of salad you are buying).
Our typical meal prep consists of:
make a fresh big smoothie each day for breakfast with greens, fruits, nuts, etc. Very delicious, portable, and can add different ingredients based on your goals. Ours is probably 600-700 cal per serving.
Make 3 large calorie- and carb-dense dinners each week (1 on monday night, again Wednesday night, and on friday night) and eat leftovers for subsequent lunches and dinners. We will usually have 2 types of leftovers at any one time so we can change it up.
Some examples of big meals we make:
Chicken broccoli alfredo pasta (full fat white sauce!)
Stew with potatoes, veggies, and venison
Stew over mashed potatoes (using full fat dairy in the mash)
slow cooker curry with broccoli and sweet potato
capreze pasta salad (pasta, basil, mozzerella cheese, tomatoes, dressing)
pork burritos (pork, rice, greens, veggies, tortilla)
keilbasa hash over noodles
veggie pilaf with braised meat over top
sweet potato, quinoa, and black bean salad
chicken donburi (rice, veggies, chicken, and eggs)
chicken chow mein
pad thai
pesto pasta with chicken, sweet potatoes, red onions, and green beans
creamy tortellini soup (sausage, veggies, cream broth, spinach)
baked ziti with meat sauce
Moroccan chicken over couscous
homemade garbage pizza
chili and corn bread
jumbalaya (sausage, shrimp, beans, grains, veggies)
Chicken risotto
Stroganoff
You'll notice a theme of lots of carbs (potatoes, pasta, grains, rice), which has the benefit of being both necessary for training and you can pad out your meals to be cheaper, as well.
If you get good, sturdy containers with spill-proof covers, its easy to fill them up after you make the food to be set aside for lunches, and then store the rest in a big container for your upcoming dinners. Then in the morning all you have to do is grab a ready-to-go lunch on your way out the door.
edit: I may be off base, but I think that the portions/types of food served in a dining cafe at work aren't geared towards the needs of athletes. The omlete they serve may be low-fat or they take out half the yolks or something, or it might simply be not be a big enough portion for you. Eggs should be quite filling and the fact that you are hungry right away afterward sounds like the omlete isn't enough for your body. Taking your main meals into your own hands might give you better (and more filling) results. Then you can use your subsidization in the dining hall for snacks like yogurt, oats, fruit, etc.
I find tracking my activity (calories burned) and my food intake helpful to know if I'm eating enough. Nothing rigorous or precisely measured, mostly I just guestimate and go based on how I feel (run down/tired, or energetic?).