Not necessarily a cause of disease.
When shrimp die, they loose the pigment under the shell turning them an orange like when you see when you cook prawns to eat.
The colour you see on shrimp is under the shell (notice when they moult, they don't loose colour), and when this colour pigment is destroyed, they turn orange.
What you are seeing is normal for a dead shrimp. But if you see a live shrimp with pale orange internals, than that could be an internal infection caused by disease.
Okay, an update: my fiancee pointed out that all of the dead shrimp have bright pink/orange internal organs, which they did not have previously. After a brief google search, it could potentially be some sort of disease? If so, do I need to dump the entire tank before starting a fresh cycle? It's a planted tank so it'd be a bit more of a pain to drain I would think. Now I'm thinking, if it isn't the drip acclimation problem or the water hardness (so many potential issues), the new shrimp may have been infected and passed it on to the older shrimp.
I did not drip acclimate them; that was probably at least part of it, huh? Good to know about dripping in the water during maintenance as well! Unfortunately, over the night, the remaining two shrimp died as well 😞 It's very disappointing, but I've learned a lot and I know a lot of what to change for the future batch. They are neocaridina, and that video was very helpful, thank you!! I've watched shrimp keeping videos before, but that was the most thorough and easy to understand, so I appreciate it 🙂 I will definitely also get KH/TDS/GH testers in addition to the pH/ammonia/nitrite/nitrate I already have.