Nice collection Drew.
I had and used to bloom a number of Dendrobiums related to yours. Dendrobium thyrsiflorum is simple if you live in a wet-dry monsoon climate, tricky elsewhere. Indoors, the sunniest spot possible. Outdoors, at least 4 hours of direct sun, or very bright dappled sun. It likes more light than what a Cattleya would like. Might take all day full sun if there is a constant breeze. Because of its high light demand, I prefer to grow them outdoors for the summer. Under lights doesn't work as well.
Grow in an open mix that does hold some water. I like a hanging basket. When actively growing usually April thru to October, it wants water, daily. The basket keeps air to the roots. Fertilize from beginning of new growth in spring until about 4 or 5 months have passed, I stop fertilizing nobile & densiflora type Dendrobiums about Aug 1. Stop fertilizer before new growth is mature. You will know when growth is mature, the growing tip becomes blunt, and ends in a single leaf, instead of a tuft of leaves. Or, if you are not sure, figure a 3 - 4 months with fertilizer, first half of the vegetative cycle.
When night temperatures begin dropping into the middle 40's F (+4 to +8 C) dry the plant out. If it is a mature plant it can handle a total drought for 4 or more months. Whenever it is cool, below 50 F (+8 C) keep it dry. Bring inside or into protection before danger of frost. Keep dry and sunny. Sometime after the first of the new year you will see new growth emerge from the base of the plant, let it get above the mix, maybe half an inch (1.0+ cm) and then resume watering and fertilizer. New growth is a sign that it is time to grow, and water will be needed. Normally I try to keep the dry spell from November 15 to February 15, though the dry spell should not end until you see new vegetative growth start. I have had some stay dormant from November to May before they wake up. Some don't seem to take a rest at all. Individual results will vary even within the species. Forcing a minimum of 2 months of drought seems to keep them blooming on schedule.
It is supposed to be a spring bloomer. though sometimes plants don't read the books, so they do what they want. Do try to observe the maturity of the current year's new pseudobulbs and use that to decide if it is time to be dry or time to be wet. Where it comes from, the dry season will be 3 to 4 months, but fog and dew at night can often provide moisture, so if you see pseudobulbs getting real wrinkly, give them a light misting or let them catch some rain. Young and small plants will need water during the dry season. If it is less than 5 pseudobulbs consider it a young plant. Cold alone can set flower buds, but do not frost this plant. If you don't get cold, the dry spell can set the flower buds, so if you don't drop below 60 F. at night the dry spell can set the flower buds. If you see flower buds form during the dry spell, ignore them, don't start watering. The plant likes to flower before the rains come, reason, the insect pollinators can't fly well in the heavy rain. So don't start watering until the flower buds are fully developed and just about to open, then give it a good soak, keep dry after that soak until new growth appears at the base of the plant.
Whew, a lot to read. Looks complicated. Most of this can be solved by where you hang your basket of Dendrobium. I move mine twice a year. Out in spring, back in late October. It isn't difficult once you get the pattern down. Good luck, and may you get the thousands of flowers a specimen thyrsiflorum can give you.