Help- tomatoes dying fast!

[Tracydr]

I've lost 5 tomatoes and 4 Chiquilteberries in 2 days. I also have several more neighboring tomatoes with leaf curl. The soil, when I pulled up the plants was loaded with white mold and very hot. I'm not sure if it's just hot because it's been hot or if the mold is making it hotter. Soil drains well, I water for 15 minutes with a soaker hose every third day. Soil is slightly damp, not wet. Had about an inch of rain last week.
This is a new raised bed with clay soil mixed with very composted straight horse manure ( no stall bedding). Mulch is mostly pine straw with a bit of rice hulls and old alfalfa hay. Recently side dressed with about 1/2 lb of alfalfa pellets per plant, on top of mulch, most of which hasn't been decomposed yet as I hadn't had time to water and soak them yet.
The effected side of the garden is the southwest. Garden has a top shade of a white sheet but this side gets a lot of of sun until later from the side. It's also a couple of feet from a concrete, seven foot block wall which really radiates heat.the plant on the very corner has been the least thrifty all summer, probably due to the heat.
It's been hot. Yesterday was about 111. We had a week of temps with the high only 100 and low of low 70s but before that it was 115 daily for two weeks with one day of 121 and the past few days it's been 105-110 with lows in the mid 80s. Monsoon started two weeks ago with slightly higher humidity and the two rains, giving the inch of rain.
I'm going out right now, plan to drench the corner that I pulled plants with 10% bleach. Will drench the rest of the bed with Serenade. Wondering if a bit of fertilizer, maybe with some phosphorous would help? I noticed that the Armenian cucumber and oregano in this bed got a little yellow after the rain. I gave the cucumber some Super Bloom Booster and it greened up nicely.
Please help! I now know what it's like to have something as devastating as late blight. I'm just thankful my pal t's aren't loaded with tomatoes right now, they've slowed down for the summer.
Wondering about using corn meal and possibly planting a grain cover crop in the area that I've emptied, if that would help? Maybe amaranth or corn?