Hi!
Pretty interesting stuff your are doing there, but I don't think TNET will be of any use for you. TNET is a network library to make the communication between different instances of unity games easier. While what you are looking for is TCP/IP communication. This is possible with the System.Net.Sockets namespace. Maybe there is already a .NET library covering the MATLAB communications over TCP/IP in that case you can just plug that dll into unity.
So to conclude, I think TNET is on a higher layer abstracting the network communication between the same game. While you need communications between different applications using TCP/IP which is standard available in Unity.