Fusarium can be seedborne, IIRC.

YUP! As Dave says...root problems IMO. I do not see Fusarium symptoms.

i think it's impossible to over-water in a 5 gallon container with a plant that large. it will drink all the water that container can hold in a day. another problem with using small pots with a large plant is maintaining enough fertilizer in it. that plant would require a mild feeding at least every other watering. despite not being in an ideal container, to me, it looks more like poison/disease due to the color of the vine.

I took Dave's advice, I went ahead and removed the funky leaves, watered it and fertilized it. Time will tell if it gets better. Not a huge loss as it only had about 5 tomatoes on it. Definitely makes me realize that some plants are not suited for that small of a container. I have a brandywine that's in the same size container and might be showing some symptoms, though not as bad, so I'll see what happens with that one too. Thanks

I am relatively new to tomato gardening (since I retired), but I have notice that that kind of yellowing, is normal in the lower branches and have to be trimmed constantly.

If I don't do "maintenance" on them for a week, my group of early girls look very similar.

trim them off and away they go.

new growth then starts from the bottom

You could try watering with Epsom Salts, 1 tablespoon to a gallon, especially if you are using MG fertilizer. I had the yellows on my container plants one year and it really helped.

Linda