Returning a dog back to owner early???

So we received a shih Tzu dog this morning and already its urinated on our carpets nearly a dozen time, even though we setup pee pads as directed by owner. It's getting to the point where we had to barricade the dog in an area where there is tile, such as the kitchen, and now it will not stop barking. This dog cannot go 10 minutes unsupervised or else it will urinate everywhere.

Has anyone returned a dog early?? How do we go about this and what if the owner is away already??