Enabling Multiple Network Interfaces

My understanding is that Tails only allows one network interface to be active, and ensures that interface is connected to Tor. I'm wondering if there is a way to override this behavior.

Some context: I'm creating a low-cost data diode, that is, a one-way network device. Data diodes are used in security sensitive environments (e.g., nuclear power plants), but my idea is to build one for journalists. If a journalist receives a potentially malicious file, they can send it through the one-way network to an isolated workstation and open it there. If the isolated workstation is compromised, it cannot exfiltrate data due to the one-way network connection. See my recent paper for more details.

To summarize, the setup I'm trying to build is:

The Internet <---> Tor <---> Tor-Connected Tails Workstation ---> Isolated Tails Workstation

The Tor-Connected Workstation should have one network interface connected to Tor, and one interface connected to the data diode (i.e., the one-way network). The Isolated Workstation should only have a connection to the data diode. However this configuration isn't possible, because Tails ensures that only one network interface is active at a time. If I try to manually enable a second interface for use with the data diode, Tails automatically disables the Tor-connected interface.

Are there some commands I can use to override Tails's default behavior, to achieve the setup depicted above?

Thanks! -Peter