No, it is not possible for them to have a child with dry earwax. In order for them to have a child with dry earwax, the child must have two recessive alleles in that trait. As the father is the only one who has one, there will be a 50% chance of heterozygous offspring, and a 50% chance of homozygous offspring in the dominant allele - no homozygous offspring in the recessive allele.