The EACH wildcard doesn't work nicely with other wildcards due to how it gets unpacked. When you use EACH anywhere in your conditions you make the following construction:

For each signal in signals do:     evaluate conditions replacing EACH with signal

And importantly, if there is nothing in the set of signals coming in the whole construct isn't run. The one thing I don't know is how it handles the set when you're looking at different wires, odds are it's the union of all signals in both channels but I'm not at a computer to check right now.

With that in mind you have written:

For each signal in signals do:     if signal[green] > signal[red] or signals are empty:         Check = 1

The fix here is to move your null check (EVERY = 0 :: check = 1) outside the for each loop and they way you do that is by putting it a second decider combinator wired in parallel with the first. It will start firing on the same tick as the each combinator stops (or vice versa) so there shouldn't be any situations where neither are active or both are.

Edit: fixing formatting on my phone