I would try hummus, for a while it was the only thing my daughter would eat. I even started making my own to get some flavour variation going. (It’s also the only thing that really kept her feeling full). For my youngest she would go for anything soft, cheesy egg pudding being a fan favourite. Teeth coming in sucks, being sick sucks, ear infections suck. Like you said it’s probably all of it.
My son doesn’t like to eat when his molars are coming in and sounds exactly like yours. We try to give him soft foods. Mashed potatoes, yogurt melts, stuff like that. Homo milk is also good because it does have some nutrients. Just try to stay calm and know this won’t last forever!! If it gets too worrisome then I’d suggest making a dr appointment