i think, they can't deny you the internship due to future expiration date . see the below:
NOTE: You cannot refuse to accept a document because it has a future expiration date. You must accept any document (from List A or List C) listed on Form I-9 that on its face reasonably appears to be genuine and to relate to the person presenting it. To do otherwise could be an unfair immigration-related employment practice in violation of the anti-discrimination provision of the INA.