Sorry, if you're looking for a definitive answer, I can't really help you there.
The Photon red LED (nichia?) is supposed to be 630nm. Looking at the spectograph charts at the ledmuseum, it looks like most around 650nm. Going by the chart I've linked above, the black/white light detecting rhodopsin in the rods in your eyes (which are responsible for "night vision) can't detect above 600nm or so, which would be orange. But the problem with orange or red-orange would be that although the peak might be beyond the detection range of rhodopsin, there might still be some low-power wavelength light that the rods can still detect. Presumably, this could also be a problem with pure red LEDs. More likely, it's the destruction of photopsin 1 (the long wavelength/red on the chart) that causes aparent night-blindness.
You can see this when you shine LEDs into your eye. When you hit your eye with a bright light source, you see spots. These spots are where the photopsins were destroyed and need to replenish. Shine a bright, white light in your eye, and you'll see spots for quite a while. That's because rhodopsin was destroyed, and this stuff takes a while to build back up. Which is why "night vision" is best after being in darkness for .5-1.5 hours. With so much rhodopsin built up, your eyes become very sensitive to even the slightest bit of light (like a dim star you wouldn't see otherwise).
Hit yourself with a green LED, and you'll see green spots, and you'll see them for quite a while. This is because both rhodopsin in the rods, and the photopsin in the cones were both destroyed. Now try it with a red LED. You'll see red spots, but these will go away much, much quicker than the white or green spots. That's because only the photopsins in the cones were destroyed, but the rhodopsin in the rods were unaffected. For an interesting experiment, try hitting yourself with a different color in each eye (red in one, green in another, for example) at the same time. The red will go away fairly quickly, while the other color will linger for much longer, even several minutes longer (please don't shine a M3 or something in your eye, a 5mm white will do).
I don't have a red-orange or amber LED, so I can't do this experiment myself with those (just green, red, and white are handy--I'm not shining my violet or UV in my eyes).
Remember, that the photopsins in the cones work the same way as the rhodopsin in your eyes, so you can indeed blind yourself with even the longest wavelength red, but your true "night vision" will remain, and the photopsins in the cones replenish much quicker.
As for the reds themselves, I can only go by what I've read and what my dad has told me from his experience. Bright, direct red light can cause temporary spots in your eyes, and presumably, can destroy a surplus of build up in the same way night vision is gained by a build-up of rhodopsin. And although these photopsins replenish much quicker, it could still take "a while". I have no idea how long it takes, and although it's quicker than rhodopsin, it might still take several minutes to build up a "night-vision-esque" surplus.
If you were wondering how avid an astronomer my dad is, he's a master optician, has built his own telescopes for years (and for other people), was the President of the Tucson astronomy club (TAAA) for 3 years, president of clubs in CO and IL, etc, etc, etc, and is in the Guiness Book for having built the largest lens in the world. He knows his stuff.
If he tells me red hurts night vision, I believe it, no matter what the charts and encylopedia entries say.
In any case, red should still be the best and least damaging to your true night vision. I honestly can't say if red-orange or even amber is "OK", but it'll still be better than white or green. Green
will not preserve your night vision.
If you doubt that red is the best (and only) option for truely preserving night vision, go to a star party (a gathering of astro-enthusiasts) and shine
any flashlight other than red, and see how the people react.
