I'm not in a northern state, but I have a seedling Anguloa clowesii. I got it early summer 2017. I made a few mistakes with it, but it seems to be doing well now.
Your plant is in active growth now. Even though it's early winter, you need to treat it as though it is early spring. Your plant is not large enough to flower yet, but it might be next spring. The plant can push multiple growths during warm weather, and a small plant can multiply quickly.
My first suggestion to you would be to put it into a much larger container. This is a large plant that will not do well in a small container. New growths can be dramatically larger than the older ones from which they spring, and it can grow to become a very tall plant quickly. I've seen photos of plants over a meter tall. Now that your plant is making new growth, it is a great time to repot.
You have a division; the older pseudobulb gives you an idea of how large they should be. Look at the size of the leaves and the small pseudobulb producing them. Keep that in mind as your plant grows.
Older pseudobulbs don't last many years. They die and dry up. Divisions should rapidly achieve growths as large as the original division, or the plant is not being well grown. I think the growth with leaves on your plant should have become much larger than it is now, but the pot is too small.
Sphagnum moss is OK for medium. The plant must stay quite wet when it is pushing new growth, or the new growth will die quickly. The sphagnum in your photo is much drier than I would ever let one get while making new growth.
Mine came with a large new growth and expanding leaves. It was potted in sphagnum. I let it get too dry just twice, and the new growth turned black and died. I next moved it to semi-hydroponic culture. The pot is 6 inches / 15cm wide and deep. After a month or so it began making another growth, which you can see in the photo:
It now looks best when I water it every day or two.
When the plant is on a normal schedule and goes deciduous for the winter, it is fine to let it get nearly dry between waterings, but you must not do this while it is pushing new growth.
It is extremely susceptible to spider mites. Be on the watch all the time.
When in leaf, it does much better with the highest humidity you can give it. During summer I put it just a few feet / 1 meter from my evaporative cooler. It really seemed to enjoy the somewhat cooled, very humid air, and a spot like this will decrease the risk of spider mite attack. I would think this plant, while in leaf, would be difficult in a typical central-heat northern home without some extra humidity from a humidifier.
It should do well outdoors in the summer when humidity is high. It will take some dappled sun, perhaps even quite a bit of sun on days that aren't too hot.
When I look up plants online I copy the URL and text into a text file so I can read later. When I was contemplating buying this plant I found the following links useful:
Tulips by Quite Another Name: Anguloa Culture at the American Orchid Society
Anguloa clowesii presented by Orchids Limited
Anguloa-new to me
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