If it is a cot you may find it near the pen in the morning. If it is a Bob, listen for it. You may hear it if it is a male. They hide wonderfully. But they tend not to go very far.
Coturnix are a lot easier to catch. You might catch them tonight. Make sure they can see the food. They are most likely in a fence line or under a large bush or honeysuckle.
Be sure and look for em early in the am as they will likely come close or near the pen they escaped from. I would offer a guess of finding it greater than 50%. They will hide very well tonight, hopefully nothing will get em.