
I think if she was my baby, I'd keep to the large cage. At 14 weeks she's still very young & it's a lot to expect her to be clean every night - although I know a lot of pups are at her age.
You don't want her to think it's acceptable to go to the toilet in her cage, but i also think she should have an area where she can relieve herself if she needs to. You may find that when she needs to go in the night & is in her smaller cage, she may feel dirty & upset by soiling her bed.
I'd give her the bigger cage, so she's got the chance to go if she needs to.
I'm sure before long, she'll start to be clean overnight, every night at which point you could introduce her to the small cage again. :)