Fusarium diagnosis help

[strawbaleking]

Hi, I need help with Fusarium.
I took these photos today. My history is I have had in the past few years tomato plants that are not hybrids with F tolerance, yellowing leaves, later wilting, browning and mostly a zombie plant once that happens. I live near Sacramento, CA and it gets pretty hot and dry.
The plants year after year get hit around the same time, end of July early August after giving good production. The fruits are never affected.
My black tomatoes don't get the yellows, they just start crisping up from the bottom sometimes on one side. Non blacks do get the yellows but sometimes not yellow but just a lightening of leaves then wilting. Always later with the wilting. Do black varieties react differently to Fusarium?
My Pink Berkeley Tie Dye(black krim genes), my first year this year, grew a few, all dying. Just like all the russian blacks for me like Black Krim or Paul Robeson always die. Cherokee derived are sometimes ok. Cherokee Carbon is ok right now. Last year Dana Dusky Rose, Bear Creek, Indian Stripe, Vorlon, or JD Special(the early girl parent VF must help) those did not die since I started those kind in the last 3 years but it was super hot like most days 100 last year and got very low production. Though Big Beef was fine last year and got to eat a good amount. But I longed for the others....
What has frightened me is that for the first time ever, my Big Beef and Whoppers started wilting bad, end of July, no leave issues at all. Huge productivity till the wilting happened quickly over a week. I was worried about bacterial wilt, but there was no milky output in a clear jar of water of multiple stems after waiting. Those hybrids did not recover and were pulled. I have no photos of those, they were just wilting. After pulling them the roots showed no nematodes nodules, no damage from critters(or me), and normal moisture levels. So I am stumped and worried of course about next year. I have read Bills B54Red exploits for years THANKS BILL! for all the info you take the time to write about everything.
I did try a little grafting a couple years ago, did very badly. I tried again this year and did get 50% to make it. However these were trial grafting sessions, so I used Big Beef as root stock. I bought nursery plants and grafted from those choices. Big Beef to Big Boy(why? I like the texture but not so much the taste sometimes), BB to Brandy Boy(those always died of Fusarium in past years), and BB to Mule Team. All those grafts plus the non grafts like Goliath(original 1800s version) are showing fusarium or what looks like it in the pictures below. I hate to think I have the 3rd race of Fusarium now with the Big Beef and Whopper CR Imp wilts. Keeping fingers crossed Cherokee Carbon stays up. I really did love PBTD. Does GGWT get a bigger longer lasting plant?
So here are some photos. The stems do have brown vascular damage somewhat on a few stems. Some stems are almost hollow. The leaves just look sick and I cannot really tell if there is a foliage disease. I water by timed drip lines. I used Trichoderma and MycoStop and general good probiotics and used Tomato Tone with some occasional liquid kelp. Again, every single plant was thriving from April to end of July them wham. July is brutal here.
Thanks,
Gary