What is your husband's semen report?
A germ cell tumor which has not affected the testes, should not be associated with the changes in semen. Though, as you mentioned chemotherapy can affect the sperm counts and their motility. Whenever the fertility issues arise, both the partners should be evaluated. So a semen test which is not very expensive can guide if only one partner needs medical attention or both. Especially with a history of chemotherapy.
I hope this was helpful to you. If it was, please remember to ACCEPT the answer so I can get compensated for my work. if you have any more questions, please feel free to ask. I am truly privileged to help you, and I want to make sure that you are satisfied with your answer.