Nobile Dendrobium will take a lot of abuse.
I handle a 1000 or more each year and will re-pot while they are in bloom without any fear of bud lose.
You do not have much to fear in moving it.
I am surprised that you have only 2 buds on a large plant. My 4 inch pots are producing 30-40 flowers. Did you stop fertilizer after August? Too much (any amount can be too much for a Nobile) nitrogen will prevent the growth of flowers. The Nitrogen causes growth especially keiki growth at the expense of flowers.