The flowers are approximately 2" in diameter and there are 5 petals (sepals) The two alternating petals are a mottled lavender and the other three sepals are pastel white. The lower lips is light, mottled lavender leading to a pastel white throat. The column is pale yellow. What do I have?

I wish I could help you, but I honestly don't know.

Perhaps someone else grows this?

Edited to add: I just saw that you are a member of the AOS and you do grow very nice Orchids! Hopefully we might see more of you here on our Orchid forum!!
The welcome mat is laid out.

Thanks, Ursula. I am new to the site and hope to be able to add something to the orchid forum. I am a hobbyist who loves to grow tropicals, and now that I am fully retired, I decided to sell some of what I grow.

This dendrobium is propably a 5-7 year old plant that was given to me by one of my patients. The plant was in sad shape and the lady said it would surely die if I did not take it. It was divided for the first time last fall (3 divisions) and one of the divisions is now blooming. The "mother" plant has 24" canes and is about to bloom as well. It looks like it will have several stalks. Needless to say, the lady-patient did not keep the label (if there ever was an accurate label), so I have never known what it is. My research has not turned up a dendobium with the petals one color and the septals another, but I will keep looking. If have over 200 orchid plants and as the bloom, many for the first time, I will post the flowers for everyone to enjoy. I have some gorgeous ones in bloom right now and one is not only a first-time bloomer but I don't think a picture of this hybrid has been published, at least so far as I can tell. It was a cross with self and you never know what that bloom will turn out to be. Stay tuned for more pics.

Ken This is C. Hardyana 'Exotic Orchids' x self and there are five blossoms here.

Oh my! That is gorgeous!!
Definitely looking forwards to seeing more.