Oh, sad to say but I doubt it. Leaves are growing, photosynthesis is occurring but the roots are not there to absorb water and nutrients nor store food and nutrients. There is an extreme slight chance that it is functioning as a propagation cutting, but with that you want the energy to go to the root development and not leaves and buds... but you never know.
Given I didn't think so what I might a suggested is salvaging some of it to do some cuttings so you can make some use of the original plant?
Dappled willow can be propagated from softwood or semi hardwood cuttings. To produce new plants, just plant 8” cuttings of stem without leaves into consistently moist soil in a small pot or nursery bed, they will generally root easily. When the roots become visible through the drainage hole in the pot they are ready to plant in the ground. Willows root fairly quickly, and cuttings potted in October should be ready the following spring. Full grown dappled willows also transplants quite successfully. A large plant should be cut back to about 12” in very early spring or late Autumn, then moved to a new planting hole.
So there might be a little hope that it is functioning as a propagation cutting (as you had a piece and stuck it back in the soil) but had to tell. Note that budding and flowering can also be stress responses. At this point you might just tend to it as a cutting (keep soil lightly moist, minimize foliage to reduce energy spend on leaves and buds so more to roots, try and moderate temperature exposure) and as possible and see what happens. ... Or whack it up into pieces for cuttings?