Yes, the clear with black in them are viable. ( I believe I saw the eyes in one of the eggs.
) Get yourself a good magnifying glass so you can see inside the eggs. ( I get mine from places like The Dollar Store or Harbor freight if you have them up your way.) They are cheap but they have that small section which is high magnification so you can see in almost as good as using a microscope.
To answer your question about light and infusoria, NOPE, it needs the light. I have used incandescent lights in the past but since they are almost extinct now, you'd need to use a bulb emitting a range of sunlight rays if you have no natural sunlight to work with through a window.
I spoke with a friend up in St John who bred many species of rainbowfish and he remembers the gurtrude going straight to newly hatched brine shrimp so you may not need the infusoria after all. He got the eggs from a company near Montreal called Aquarium Direct. Here's their brine shrimp eggs page:
https://aquariumdirect.ca/en/search?controller=search&s=brine+shrimp+eggs
These shrimps apparently are smaller in size than the usual San Francisco Bay or Great Salt Lake brands eggs. One thing when using newly hatched brine shrimp, they are their most nutritious for the first 6 hours +/- after they have hatched so you want to time their hatching with your feeding schedule. In my hatcheries, since I fed 3 times a day, I had 3 different batches of eggs hatching at 3 different times so that they were as newly hatched as possible at feeding times. You'll want to hatch a small sample of eggs to see how long it takes to get them to hatch so you can time it for your schedule. No need to pre-make them.
Now, just to confuse you a little more.
you have another option and that is to use the decapsulated brine shrimp eggs. These will not hatch and fish fry are supposed to feed on them. I say "supposed to" because some fry need to see the movement of the food to stimulate the feeding reflex. I have tried using the decaps with mixed success which is why I stay with hatching them out.
So there you have your options.