Let's say you have an old corpse (which could be a skeleton) that didn't die from old age, and that your mage casts a Restore Corpse, whose effect is:
You grow flesh on a decomposed or skeletonized corpse of a Medium or smaller creature, providing it with sufficient flesh that it can be animated as a zombie rather than a skeleton. The corpse looks as it did when the creature died. The new flesh is somewhat rotted and not fit for eating.
Can this corpse be brought back to life, despite having been dead for a bit of time and/or having been dramatically altered (decomposed, eaten, etc.)?