If your provider is simply doing a POC cup, then you would use CPT: 80300
HCPCS: G0434, but remember POC cups really should not be used to make medical decisions. This even says it on the instructions for the cups.
Your provider should consider using a lab like Cordant Health solutions to send out for screen to confirm, he can still bill for reading the cups and and doing the testing in house and the lab can bill for the screen.