Marilyn, remember plants want to survive. T. Begonias stems, leaves and flowers, grow from little spots, called eyes, that form from the tuber. If the tuber is large enough, often a result of age and health, the tuber will sprout more eyes; small tubers often have more that one eye that will produce stems+. (My 7 yr old tuber has 5 stems just starting & I have not yet covered it with soil). The stem with ornaments looks as if it will also produce new leaves--my opinion. Be hopeful.
Don't know how to prevent chipmunks from destroying plants, other than fencing. Remember, chipmunks also want to survive.