It seems like it would really depend on the difference between the two skis. If they're both rocker/camber, only one is slightly more cambered... I think you'd be hard pressed to get any kind of a refund for the difference. However, if one is clearly cambered, and the other is just about flat, then your skis are going to ski totally differently. If that's the case, I could see the manufacturer giving you a warranty on them. The issue you'd end up facing though, is that typically warranties go through the shop you purchased from. If the shop is closed already, it could get tricky.
I think your next move should be to snap a few photos that really highlight the difference between the two skis. Then I'd either throw them up here to get some more opinions, or just get in touch with the shop directly to hear their opinions. Again, if the difference is slight, I wouldn't worry about the hassle of getting them warrantied. If however, you have one cambered ski and one non-cambered ski, then that's definitely cause for concern.
Hope this helps, and feel free to shoot me a private message if you have any other questions/concerns regarding how shops handle warranties!
Matt @ Skiessentials.com