In my case, my CH340G is also working, I can update the firmware via USB. Just the LCD and the valves are not working. I haven’t tried the relay yet but I assume it is not working.
I doubt it has anything to do with the circuit trace, I have checked the connectivities multiple times using a multi meter. I suspected the µC, I have reprogrammed it, also replaced it, still the same thing.
So I can borrow a o’scope, do you know what to look for using an o’scope?