Well, I hope your renders got out on time, but two quick suggestion I can make is to first, try deleting any lights in the scene. Sometimes lights become corrupt and cause a scene to not render. If that doesnt work, a last resort would be to go to Extensions> V-Ray> Debugging> Regenerate all materials. You'll have to re-build all your materials from the base diffuse layer up, but the model should render again.
Let me know how it goes with the model.