Yes, a good grating will see the line. If its weak, its only visible during warmup. for reasons unknown. If its strong, its distinctive and can flicker...
The people who had tubes exhibiting it, well some of those tubes got sadly broken during handling.
There are only a few lasers left in the world showing this line, and we still do not have a second, verified, accurate wavenumber for it.
If you have a tube showing this line, Dr. Sam Goldwasser and I am very interested. A large spectrometer may end up on your doorstep if you have a tube showing the line.
I finally have something that can do the measurement.

Steve