I still stand by my belief that the on screen ESB visor is in fact smoked. The screenshots I have provided on the Executor and in the Carbonite Freezing Chamber lead me to believe this to be true. Whereas you can see Boba's neckseal behind a smoked visor, not a green one. In the Carbonite Freezing Chamber, we can see the blue background teeming through the visor; if this were green we would see the hue, instead pure blue.
Your assumptions are incorrect. The tour photo I posted above shows his white neck seal without a hint of green; It looks almost exactly like the screen caps you posted.
The only time we can definitely see the visor is green is when it is photographed from a close distance with flash. Any other photographs that have light passing through the visor show the same smoky effect we see in the screencaps.
From your comparison, notice how the entire scene, including Fett's helmet, has a heavy blue cast. This is due to the lighting gels and Lowry's digitial color correction. You can see the helmet colors in the screen grab are very different than the tour photo for that reason.
My speculation is that the crack has everything to do with the visor being replaced. The crack probably destroyed the visor inside, since it was used for stunts in ROTJ. The monstrous crack seeping from the visor area that appears after ESB is my best guess to why it was replaced.
Other ILM Fett helmets, including fan-made helmets, have a crack in the same area; it's a weak point due to the helmet design.
Also, the ESB hero was not used in ROTJ. There are two ILM ESB-style stunt helmets that we have seen, and it is more than likely that one of those two helmets was used for ROTJ stunt scenes.
To me, the ESB/ESB helmet and the ESB/ROTJ/SE helmet are two completely different things. The helmet used in ROTJ and many promotional shots does have numerous differences, for one the noticeable extra scratches, the blue marker littered on it, and the large crack on the left side of the visor.
Saying the ESB and post-filming ESB helmet "two completely different" things is a gross exaggeration. There are additional, small sliver marks and a couple slightly damaged cracked spots—but not very many. The blue marker is just bizarre, but the sum of these differences doesn't make the helmet "completely different." It's fairly easy to spot the weathering and cracks that weren't present on the helmet during filming and to omit them from a build-up/paint-up if one is so inclined.
the Boba costume was completely modified and changed in all sorts of ways.
Again, this statement is not accurate. There are variations on each of the original six suits due to the progression of the costume's development. What we are seeing on tour is parts of six completed costumes that are now jumbled all over the place.
As for ESB, ROTJ, or SE costume accuracy, I believe the only version that should have the green visor would be SE.
As matter of individual preference, everyone is free to use whatever color visor they prefer. Though if one is concerned with accuracy, our best reference weighs heavily toward green visors for ESB and SE.
Here are two more examples of the post-filming (SE, if you will) ESB helmet showing what "resembles" a smoky visor (again, we know this visor is green):