What do you consider successful. I'd love to see these shade grown tomato plants. Personally, Ive never even seen tomatoes for sale in the grocery from Florida.
I have farmed both coastal and inland foothills here in San Diego. There's a reason no commercial tomato grows are along the foggy marine layered coast. If you're saying shade is no problem for tomato production, then show me the evidence.
Also, yes there are a lot of successful greenhouse tomato grows in pots. But, what's the growing medium and how large is the pot?
The most concerning part of this whole post is no one mentioned the variety of tomato being grown. So yes, case closed. Bugs killed a plant put in the wrong location.
I have seen tomatoes grown very successfully in pots here in Florida (where nematodes can be a limiting factor for in-ground plants). I have also grown cherry, grape, and Campari tomatoes in shade (in the ground). I don't see any signs of a leaf disease like septoria, or early/late blight. I would be looking at a soil borne disease like fusarium or verticulum. If the plant dies, cut into the stem and look for brown dead streaks in the stem. I would also think that one of those is more likely if you have been growing the plant in the same medium as a diseased plant from before. Fresh plants in fresh soil would likely help for next year (we've passed the time to plant here in Florida now).
Idk if you're aware, but your posts come off as needlessly aggressive. You were wrong, his problem is mites not what you said, and you're perpetuating myths like water on tomato leaves causing sunburn... Now still trying to argue that you were right. Anyway, here's my local university's master gardener program saying to shade your tomatoes:
https://ccmg.ucanr.edu/EdibleGardening/Protecting_Tomatoes_during_Hot_Summer_Days/