Is tungsten gas visible?
You can easily see it: "burn out" the filament of an incandescent lamp from a flashlight (torch) with over-voltage (e.g. put a 1.5 volt lamp across a 12 volt battery). The bluish flash you see is vaporizing tungsten (W), but to the unaided human eye, it looks little different from, say, the "spark" in xenon flash lamps.

Since the filament is so hot, it radiates heat rapidly and cools quickly, so is visible only as a flash. If you were to vaporize a few kg of W, it would be visible longer as a blindingly-bright object.

BTW, notice the film on the "dead" lamp: it is condensed W. If the lamp has a vacuum, the film is silvery, but collision with argon or other inert filler makes it rougher, or grayish.