Systems, devices, and technical methods of the present disclosure use an edge appliance to facilitate seamless interoperability between a cloud emergency call management system and call-center systems that are situated onsite in an emergency call center. When an emergency call is received from a caller device, the CECMS routes the call to a call taker who may be working remotely on a telecommunication device. The CECMS transmits a duplicate of audio data and other data that is exchanged between the caller device and the telecommunication device during the call to the edge appliance. The edge appliance converts the audio data and the other data into formats that are compatible with the call-center systems and uses a virtual construct that represents the telecommunication device to transmit the converted data to the call-center systems through a network to which both the edge appliance and the call-center systems are connected.