Just to pull back the curtain on this Mystery Fabric a bit...
"Alcantara is composed of about 68% polyester and 32% polyurethane,[5] giving increased durability and stain resistance. The appearance and tactile feel of the material is similar to that of suede, and it may be incorrectly identified as such."
On seats, there is no danger in using a product like Folex.
On areas like pillars, headliners, etc; additional caution should be used. If steaming, keep your distance, so the adhesive backing is not over heated.
I have not tried it, but based on the composition of Alcantara; a diluted solution of Microfiber Towel Detergent should work well.