It should still move with air in the system, it will just be sluggish as the air has to compress. Repeated cycles of the controls should purge the air back the the resovoir or thru the seals eventually. Do you hear the safety relieving when you work the bucket lever? If repeated full cycles of the controls don't work and the bucket still won't move, I would look for other damage from the log, such as a smashed/flattened hard line that is restricting the flow to the bucket cylinders.
I drove a wreck damaged vehicle home for a friend one time. It wasn't that badly damaged and we looked it over pretty good. All the main safety structures appeared to be functional and it looked reasonably safe to drive till I drove it. It had no right front brake and caused a pretty heavy steering wheel pull when braking hard. During the crash, a body structure had been deformed into the suspension and chopped a brake hardline right in two. This cut and crimped both ends of the hard line. They were perfectly sealed and dry with no brake fluid leakage. We played with it for quite a while and the crimp was strong enough that it would not leak even when repeatedly stomping on the brake pedal...
