I can't advise for sure on how to remove it, but if you can't get Goo-Gone or similar, the active ingredients are petroleum solvent naphtha which is a mineral-based oil/solvent, and d-limonene, which is a common citrus-derived chemical found in a lot of citrus-based cleaning formulas. So if you look for THAT stuff in a cleaner/sticker lifter, you'll be getting something similar. Chase down the active ingredients if you can't find the actual thing.
Actual Goo-Gone is pretty safe, but there are several different kinds of petroleum naphtha, it's more of a category of stuff, and some if it is quite smelly and flammable. So be very, very careful working with it and anything that contains it.
I personally have had good results using mineral spirits and mineral oil for sticker lifting, but I don't know how that would work on pink marks OR pony vinyl, so be advised and try on a tester or something!
Good luck, and stay safe!