So the yellow, stinky stuff is called aloe latex and if you are going to consume aloe for the health benefits you want to first drain the aloe latex. The smell is normal (kind of a horrible body oder sort of smell). The latex is a powerful laxative and can really irritate your intestines. Unless you are very constipated than you want to get rid of it before eating it. I start by washing the aloe after cutting it. Cut off the ends and top of the aloe branch. Let it first sit at a 45 degree angel for 30-45 minutes. Then let it soak it soak in some water for another 20-45 minutes. This will help extract the aloe latex and leave the aloe gel. There are plenty of YouTube videos that show how to filet an aloe branch to get the gel out. But that stinky yellow substance you're smelling is natural (and naturally smells bad), nothing wrong with your aloe at all!

I've heard different things about being able to grow a new aloe plant from a leaf, so I thought I'd try it myself. Some say it can (like a typical succulent) and some say it can't. My one attempt with 5 leaves (as a test) all failed, but I also may have had too much moisture and learned more since, so I'm going to try again this season. You can do it 1,2, or 3 all in one pot, depending on the pot size and how many pots you want to be taking care of. The soil type is not optimum but I would leave it as it is what the roommate wanted. Though if you can contact the roommate and ask about changing the potting soil, then go ahead. The plant has been doing OK in that pot probably because the roommate knew about it and would water infrequently, but for the sake of learning and putting that learning to use, then moving it to a proper soil would at least eliminate any future problems.

They will grow fine together. I would have simply cut the pups off as low as possible, leaving no attached roots to avoid disturbing the parent plant's roots, and inviting a melt down. Lay the pups on their side for a week or so, then plant in dry soil, and wait for roots to form. Pups need to be large enough to survive several weeks or months without getting any water. Very small pups w may not survive. Don't repot any of these for a few days to let open wounds callous. Take your time, there is no hurry to do anything.

The Cacti and Succulent Forum may be the best place to ask your aloe questions. The search function on this forum may answer a lot of questions, too. Folks on the C&S forum recommend a gritty mix and it has worked for me. My pots (I have 12 different aloes) stayed out in the rainy summer and did well - no rotting. MG cactus soil tends to get dried out and rock hard around the roots if not amended with perlite (at least). I have never been successful at rooting an aloe leaf, but that's just me. I have trouble rooting a lot of things. These folks have helped save a lot of my succulent plants. They welcome questions and like pictures! Good luck everyone! Happy gardening!