Federated ID with SSO and Claiming Domain in Adobe Captivate Prime

We want to use a custom, external identity provider via SSO within Adobe Captivate Prime (ACP). ACP is the service provider and our custom web app will be the identity provider. We will have courses registered in ACP and we want users to authenticate with our custom web app via SSO. We will setup Federated ID identity types for the users and have looked at how you need to "Claim a Domain" for the user's email. My question is our user's emails are not all at the same domain company. The users have thousands our different domains in their emails. They all have accounts in our custom identity provider system, but have many different domains. The user emails are from our customer's companies and have registered with our product. My question is will thiswork? Or do all users have to be in the same Claimed Domain to authenticate via SSO and ACP?