the input laying on different layer will count as an opposite value, due to ferro-magnetic interaction. The order of the inputs in a truth table is not significant. Each value has the same weight.
If the inputs are A=0 B=0 C=1, and B is on a different layer, the output will be 0, indeed B is counting as 1 in the minority voter.
To obtain a majority voter an inverter after the nucleation center is enough.