I think the key words here is that these people were asked "to replicate a signal lantern found inside the H. L. Hunley" by the people who have been doing the excavation of the Hunley itself. Now that simple statement does not say that they found evidence of "blue glass lenses" or not, but by the same token we have no evidence of remains of a blue pryotechnic light being used either.

I would have to say that at this moment the percentages are that the Warren Lasch Conservation Center are the authority in this case as they have been the one to uncover the evidence that we have. We know that a lantern of the type that was replicated was a signaling device that was capable of even sending messages let alone just a simple signal. And was used by the signal corp of both North and South for just such purposes with or without any "blue lens".