Pink skin discoloration after liquid nitrogen removal of actinic keratoses (Photo)

I have some pink spots on my face after removal of actinic keratoses using liquid nitrogen. The spots are fading but still visible. In a follow-up appt the doctor said keep the spots dry so they will fade and not to use any moisturizer on them, only tretinoin and vit c serum. Keeping them dry counters much of what I have read which says to keep pink spots moisturized to help them fade. Is it helpful to keep the spots dry or should I use moisturizer on them? Would a scar cream help them fade?