3X8, Alum binds to the ionically negative (colloidal) clay. In almost all cases, the alum, while still in the stirred up clay by the dog, will make the clay settle back out very quickly.
Eventually, the dog and fish will slowly make all the alum migrate deeper into the softer silts and to the deepest portions of the pond that rarely get disturbed.
So, to answer your question, yes, it will help, but it depends on just how much and how long.
If your pond clears on it's own already, I would just broadcast Alum granules into waters 3 feet deep and shallower. I wouldn't worry about creating a slurry first.