Interesting.
Using Wolfram Quantum Framework, this AME can be tested like this:
1/36 QuantumPartialTrace[
QuantumState[N@Flatten@AME46, 6]["Bipartition", #], {1}] ==
QuantumState["UniformMixture", 36] & /@ Subsets[Range[4], {2}]
{True, True, True, True, True, True}
Directly testing all six bipartitions to be equal to the uniform mixture.