Custom Send Address on Cloud Instance

I contacted support since we are moving from on-prem to cloud. In the cloud it is not possible to have MFA codes sent from a custom mailbox. Before we were able to use our domain to send codes out using the Advanced SMTP settings. Now they are only coming from screenconnect.com no matter what. This is problematic when white-labeling a product. Please allow the same functionality the on-prem version has.