Mediation systems and methods for hybrid networks including an IMS network. A system and method mediates an IMS network having a serving call state control function (S-CSCF) for providing session control for user endpoint (UE) devices with an alternative network to create a hybrid network. A service and corresponding service request code are defined to utilize at least a subset of capabilities provided by said alternative network. The S-CSCF is provisioned to identify and receive an alternative network service request message from a UE, including providing a call model having at least one filter code to associate said alternative network service code with at least one application server (AS) dedicated to serving alternative network service requests, said AS being responsive to service point triggers (SPTs). The AS is in communication with and capable of controlling delivery of at least a subset of services provided by said alternative network. The alternative network is a wireless broadcast network, such as a DVB-H network or a forward link only (FLO) network. The IMS network and S-CSCF and ASs are provisioned to provide two-way transport for interactive services for said hybrid network. The call model for alternative network services is constructed as a dynamic call model.