Question about new sod (Centipede)

So I had all new sod put down at my new house, and i noticed that a few (may 10 total - spread out across the front/back/side) of the sod patches are completely dead (likely dead when they were put down).

Everything else is thriving due to the constant rain/sun mix he have had the past couple of weeks. Will the dead patches fill in ones the roots take off, or should I go to buy a few patches from home depot and replace them?

Yard is about 12 days old.

Also, When can I leave it alone and not have to stress about watering it? (if it ever stops raining and dries out).