Alcantara cleans up fantastically with the Vanish spray foam cleaner, cat ****** on my car seat, used that & ****** hell was it clean afterwards & no loss of quality is material either
Also I've been told by a very reliable source, get a tea towel with no print of course or cloth & have it damp only slightly & then iron the alcantara with the cloth on the seat, it basically lifts the dirt of onto the damp cloth & this is from a veteran car dealer & I trust him alot, I've heard this method before for cleaning materials/clothing so it sounds genuine