Need my root domain and a subfolder to have a untraceable subfolder payment page

Question

So do payment gateways like stripe or authorize.net have cookies or a way to track the links prior to the payment page? Let's say my payment page is domain.com/payment but I have a sepetate site and folder which is domain.com/i/payment, is there a way to make it seem like the payment was from domain.com only especially since they share the same database? Is there a way to do a null refer or something and obfuscate or hide the final payment page and thank you link? Or make it appear the payment came direct from the root folder and not the subfolder such as /i