Testing customized html Okta login

Hi, our team is currently working on customizing the Okta login page using html. Okta requires us to set up Custom URL Domain first before doing any previews or change to the html code (p1). We have set up one domain already using one of the dev account. However, it seems that okta requires each organization/dev account to set up separate custom URL domain(p2). We are just wondering is there any way to test/preview our changes to the Okta login page without creating separate domains for different dev accounts? Is there anyway our team can work together without having different domains? Thank you.

Screen Shot 2020-06-30 at 4.03.07 PM