How to correctly simulate a heat sink that was additive manufactured??

Hi everyone

Im trying to simulate and recreate some experimental data involving 2 heat sinks, one of aluminum fabricated with conventional manufacturing and the other of stainless steel with additive manufacturing. The experiment consisted in compare the performance of both in terms of heat transfer. The issue is that Im failing to match up the experimental results with the simulation where experimentally the additve manufactured one performed better and in the simulation was the other way around(You can see the result of the simulation in the attached images). I´d like to know if there is a way to properly simulate and capture the changes that additive manufacturing makes to the material of the heat sink.(I already refined the mesh and used the roughness height option and no big changes in the simulation results occured)

I appreciate any suggestions!