I have a swatchbook from Relicate that has pretty much all of the black colored Alcantara options.
9040 is probably the closest. I've found that when trying to match other cars I ran into this same problem of them only being "close" but not quite right. I believe some manufacturers use their own runs or special dyes.
It's also possible that this is Ultrasuede - another competitor to Alcantara (just a brand name after all). I don't have samples of that.