Best tip to get rid of pen and marker on dolls (My little pony)

Ok, I know it sounds like a "mommy tip", but not necessary. I got some My little Pony from Value Village to make custom ponies. One was severely drawn on with a marker and it was not noticeable in the bag with the mane hiding it.

So I scoured the internet, there must be a way to get rid of this mark. I tried all the tips including:

Dish soap (Dawn)
99% Rubbing alcohol
Baking soda & water paste
Glycerine and baby powder paste
Mr Clean Magic Eraser
Goo Gone
Drawing on with whiteboard marker (it sounded silly anyway, but I was desperate)
Acetone (pure one)
Odourless turpentine - white spirits
Lacker thinner
Hertel cleaner
Colourless marker blender
Hand Sanitizer
Goof Off

I didn't tried baby wipes: I'm not gonna buy them only for this and if acetone don't work, I don't see anything "milder" could work. Hairspray was mentioned too, but I don't use any so I chose not to try it.

The last thing on my list was acne cream. There was a problem, the site suggesting this was from the USA and they said to use a cream with 10% Benzoyl Peroxide, but in Canada, it seems that the approved dose is 5%. I was a bit skeptic it would work. So I got some Clerasil, it was the cheapest one.

I tried the method suggested.Put the cream on the markCover with plastic film (don't wrap more than one ply where the cream it)Cover painted area (aka the face in my case) with a cloth or a paper towelPut the doll in the sun for a day (outside on it front of a window).

Stain is there, not faded at all. I told myself, let's do it again, but for 2 days. Meh, nothing again. I contemplated buying some miracle stuff from the USA Remove-zit , but thought it was expensive for a small project. I decided to leave the ponies (one blue, one light purple and a yellow-orange one) by the patio door with their acne cream. It worked. The yellow-orange pony had only a light mark and it was gone, but the other two needed another round, but it faded drastically. The purple one, the worths one which I tested everything on her is as good as new. The blue one will be fin in a few days. I've read to be careful so it doesn't bleach the pony, so I prefer to re-apply often and check every few days.

My blue pony is now like new and the mark is gone forever. It take a bit of patience, but it does work in the end.