Exchange Server DAG and Failover Cluster with High Availability

I have 2 exchange servers (EXCH1 and EXCH2) that have Exchange 2013 on them. They are both on Windows Server 2012 R2 (Standard) machines. They are also a part of a DAG (Database Availability Group) (DAG1). Both servers are CAS (Client Access Server) and MAILBOX roles.

Currently, my router NAT settings are forwarding ports 25, 110, 80, and 443 to EXCH1. Would it be possible to port forward to DAG1 for these ports and let the Failover Cluster Manager decide which machine to use?

I tried Network Load Balancer, but it caot co-exist with Failover Cluster Manager.