The interior is reinforced with carbon fiber. Carbon fiber wets out in the same manner as fiberglass, however it is harder to tell when you have done it right. Unlike ‘glass which starts white and becomes clear upon saturation, CF is black and stays black. Since this boat is wood, enough epoxy must be applied to saturate the cloth and soak into the wood. The indications you have to work with are the color and reflectivity of the fabric and how it handles. For example if the cloth does not stay down or bubbles up the wood behind it is likely still dry. If the cloth is deep black with little reflectivity, it is likely under-saturated.