Those pots of porridge you can get are quite filling.
You can actually cook pasta by pouring boiling water over, adding a lid and leaving it.
What about a slow cooker at work? (don't think a hotel would like it) go in early and prep it, cook during the day, take half back to the hotel in a food flask and then leave the other half for lunch the following day.
Will he have a fridge in the hotel? If not there must be one at work.
You can get some self heating tins but not sure how healthy they would be.
What about couchsurfing? It's not just about sleeping on someone's couch, you can arrange to meet people for a meal / coffee.
How far will he be driving between the hotel and work? It is possible to cook on a car engine (food in foil secured where the engine will warm it).
Ziplock bag omelets? he might have to boil the kettle a couple of times but no reason why you couldn't do it in a kettle rather than a pan.
Check out the local kebab places, a lot sell just salad or salad in a pita bread.
Maybe think about heating rather than cooking, tins of things like soup can be heated in a kettle (heat the can before opening).
Think about tins and jars that don't go off.
So maybe a tin of tuna, some dried pasta and some sort of sauce that doesn't need refrigerating, either a small one use pesto or something like salad cream or salt and pepper.
Boil the kettle and empty into a container with the pasta, put a lid on and leave for 7mins. Open the tuna, drain and mix with the sauce.
Once the pasta is cooked drain and mix with the tune. Add a ready made salad.