The honeycomb structure inside is probably only slightly conductive, each cell thus only reflects a tiny fraction in different angles and most of the energy is absorbed. So thats cool, wondering how its done now with modern designs.
I know a little bit about this stuff, did a lot of electrodynamical simulations for my bachelor degree.
It looks like it would work, at least to me this structure makes sense for this purpose.
Honeycomb structures are commonly used in aviation, furniture, cars, sporting goods etc. It's actually quite easy to get your hands to honeycomb material, say made of aramid fiber and then clue some carbon fiber on top of it and argue that it came off what ever stealth plane you imagined up.
Stealth has lot more to it than honeycomb structure. I would even claim that if it's made out of aluminium it will shine in radar like Christmas tree in the North Korea.