Cal Spa Overflow Problem

Okay so this is long but I think it's important to get the details out there. I recently moved into a house I'm renting from my Uncle and he has a hot tub here that has always worked and we used it maybe 10 times since I moved in and everything worked beautifully. The water was kind of gross though so we turned the breaker in the garage off, drained it, scrubbed out the interior, then refilled it. Well I wasn't paying attention and when it was refilling it overflowed out the sides and the panel was still off from where we drained it which got a lot of the components wet. I drained it back to a normal level and then flipped the breaker back on and the control panel showed an SN error then after a minute or two an OH error. The heater and pumps never turned on. So I flipped the breaker back off and opened the inner panel to see the circuit board. I figured it was wet so I let it dry for a day and then flipped the breaker again. This time the tub didn't show any errors and the pumps and heater started up. The temperature read 57 degrees so I was excited it was working and decided to go about my day and let it heat up. When I got home that evening the tub was off and the breaker had been tripped. When I tried to flip the breaker on it instantly tripped again. So I opened the inner panel and unplugged each component one by one and tried the breaker each time to see if the breaker would stop tripping after I unplugged one. I'll include a picture below of the circuit board with a red box around the component I unscrewed. When I unscrewed section 2 which was holding down two wires that as far as I can tell go to the fuse and transformer, the breaker stopped tripping and stayed on. Mind you everything else had been unplugged at this point so the tub didn't do anything but the breaker didn't trip. So then I left section 2 unscrewed and plugged everything else back in then turned the breaker on and it stayed on but still nothing started up even though it wasn't being tripped. I have a repair person from Scioto Valley coming out on Thursday for $100 an hour but I would rather get some cheaper advice and help on here if that's possible. I included pictures of the circuit board below. Also, when I said breaker in this whole thing I meant the one in the garage, there is a separate GFCI breaker a couple feet from the hot tub outside but I opened it and there were just wires and stuff nothing I felt safe messing with.
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I couldn't see the wiring diagrams, they were very small. I would disconnect both power leads to the heater and reconnect everything else and run to see if it holds. Usually when you have and immediately tripping breaker it is usually the heater causing it.