| It probably won’t work and possibly could make things worse; but there is a shot.
Denatured/wood alcohol/isopropyl alcohol/methanol/ethanol. A common alcohol often will remove permanent Magic Marker from a flat surface (but not so well from a porous fibrous surface like carpet); however it’s best to treat the surface within a few minutes before the Marker fully dries. I am skeptical that alcohol will remove the Magic Marker from carpet because it’s so fibrous and porous.
If you have a spare piece of the carpet or if there is a section of the carpet that is covered by paneling or such you might want to remove a small section to expose carpet that is normally hidden and try marking a test patch with the Marker let it dry overnight and then try to remove the stain with alcohol. The reason I suggest trying it first in a test area that can’t be seen it because I suspect there is a good chance that it will smear the Magic Marker make it fade slightly but spread it to a larger area. If it works what you’ll probably have to do is to first get as much out as you can with the alcohol then while it’s still damp scrub the section with soap and water or a carpet shampooer.
I think there is also some commercial products that are sometimes called “dry cleaners” or and “spot removers” that often can be found in a supermarket or hardware store. These are typically some sort of solvent that is a little stronger than alcohol. Again I suggest if you try this type of product to try a test area that is out of sight because there is a chance that it might remove some of the pigment from the carpet or and it might smear the stain to a larger area.  |