If it is shelled, if the temperature is low (below freezing point), seven days is no problem. Yes, but it is not recommended to eat dead oysters. However, according to the freshness of the ingredients, oysters can be eaten dead as long as they are not spoiled. You can smell them first. It is best not to eat them raw when they are dead. They can be roasted or steamed.
Oysters can live for about 3-4 days when they are kept in cold storage or buried in crushed ice when they are out of water.