Email exchange integration

Hello everyone,

The client provides contact center services to its own clients, one in particular has a case where it cannot use the integration of its emails through MX and TXT records in its DNS or use SMTP. Email forwarding is also not an option.

My question is if there is any other type of email integration with email exchange like EWS or Active Sync? Those are the only options that the client is giving us. Natively we understand that there is no possibility, but is there any other way that we are not contemplating?

Like always, thank you