Bringing this back from the dead... tried these exact steps today (using woolite) and it worked like magic. I didn't have the same amount of nastiness all over the surface as the OP did but my alcantara was definitely black near the door handle from repeated opening/closing of the door. Using only one "cycle" of scrubbing with water, woolite solution and then water again to rinse it cleaned everything perfectly. Instead of using a heat gun or hair dryer I used a dry cloth to get out any excess moisture and then left the doors open to sit in the sun for ~10 mins. Awesome write up thanks!
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