Caring for Abandoned Duck Eggs?

If there are broken wild mallard duck eggs in a nest in my garden will the mother come back? She's laid about 10 eggs over almost 2 weeks. Then stayed on the nest for 2 days and left. Now it's been just about 2 more days, and a few eggs are broken and we haven't seen her. Should I try to incubate? The temps are likely to be be in the high 30s tonight.