If I send fluid to the 4930KKK and then to a 780ti, will the 780ti get roasted from the pre-boiled liquid from the 4930KKK?
The simple answer to your question is no. Liquid cooling doesn't transfer all of the heat from one component onto the next. With a good pump that can provide adequate flow of the coolant and a good radiator to provide adequate cooling, the most the coolant temperature will increase from one component to the next is maybe 1 or 2 degrees.
This.
Loop order is not important, aside from pump above reservoir physically - same thing with parallel vs series in multi-GPU configs. Negligible temp difference.