I don't understand this. Accutane is Vitamin A so how will putting pure Vitamin A on your lips help? Surely you want to avoid Vitamin A to let your body recover.
Anyway I was on accutane and it caused this as I was overusing lipbalms to help the dryness. Anyway I have been not using lip balms for months now, am living a healthy lifestyle and am leaving the skin on my lips alone as much as possible and when I do need to exfoliate to go out I use steam so no hurt is caused. Been doing this for months now and have witnessed continuous improvement and have seen the layers of skin slowly build again and I am now very nearly healed. I would avoid putting anything on your lips to be honest, there is no overnight cure it is a healing process.