Regarding the misconception that there are not enough MIDI parameters to support something like the TI, that is not correct because you can always use NRPNs (MIDI Non-Registered Parameters) instead of standard controllers (CCs) to communicate with the device. This NRPN "protocol" is part of the MIDI spec and supports thousands of parameters (up to 16,384) on a device. This is actually how the Dave Smith Instruments communicate with the SoundTower patch editors (for the Prophet '08 and Tetra, for example). Actually, on the DSI stuff, you have the option to use either CCs or NRPNs because there are so few parameters. But you could easily support something like the TI via the use of NRPNs.
The link you posted tells the MIDI CC used by NRPN are 98 and 99.
On the Virus TI MIDI implementation PDF, I can see these are both mapped to unison parameters. I can see no NRPN on other controllers numbers in this doc. Am I missing something? Does the Virus support NRPN at all?