No, you only need to upload offers from one person to get a comped cruise. However, having offers from both you and your guest can help unlock better comps or bigger discounts. Usually for your first trip, your comp will be based on whoever appears to be the bigger player's offers.
After your first trip, URComped will look at your combined play with your guest when you claim future offers and will share tips to help you get even better comps next time.
If you want your offers to be based on your combined play, you can link your URComped accounts by messaging your host.