This seems to be fixed, I'm not getting an error when trying to view in a different language... however, there aren't any translated articles atm (am working on that presently as we're almost done with the German translation for the VW3 series), all that is available is English. I assume the user attempted to look at it in English for it to do that error (clicking the Go button), though I can't be certain.
I did notice that when doing that (clicking on English > Go) I end up with an identically named page, but with no text. When I reload, I get the full article I was just looking at.
Not sure why tbh...