Legal dispute with earthworks contractor acceptance

We have a problem with the drainage. The earthworks contractor installed only one inspection shaft on the house side, opposite to where the collection shaft with the pump is located. He apparently used unsuitable sand and only after I intervened did he add new sand above the old sand. No seepage water reaches the drainage, everything is dry. Despite ventilation in the basement, mold and moisture form repeatedly. Out of fear, the earthworks contractor refused to accept the work. He claims that acceptance automatically occurred with the move-in. Therefore, the matter is now going to court. The two inlet pipes of the drainage into the shaft are dry, as is the concrete wall below the pipes. However, larger amounts of water seep into the shaft at the concrete rings of the shaft, which must be pumped out. My question is, is it normal for so much water to enter the drainage shaft from the sides through the joints of the concrete rings?