That pale color looks dead on the money for steamed Walnut in which case they count sap as allowed. We had an 1880 board foot pack of Walnut come in and the only thing I could land at the time was steamed and a lot of it was rejected (we had to buy more) that was almost identical in color to that stock. The steaming process darkens the sap and lightens the heart wood in an attempt to normalize the color (so they can sell you the sap).
Its very frustrating but on a purchase level to purchase unsteamed, all heart, your cost of material goes through the roof which is likely why they allow that material through.