Yes, it does, but it would have to be a freshly missing limb. They cannot cure/fix old, healed injuries. For regrowing a recently lost limb, it would likely take a few days of a fungus growing over the wound and then proceeding to grow into what looks like a fungal replica of the limb. After a week or two of this process, one could start to peel back the fungus to reveal a new limb beneath. That limb would be slightly off-color from the rest of the character's skin tone permanently, however.