I work in NY & live in NJ; box 16 is less than box 17 on my third party sick pay W2. This is not letting me e-file. (Note box 15 says NJ.) Should box 16 match box 1?

Box 16 is state wages which can be different than box 1, box 17 is state tax paid. Box 15 is your resident state for sick pay. It doesn't make sense for tax paid to be more than the income. Contact the issuer and ask them for a corrected form.