You need to have the engine running with the driveshaft turning the pump to have both movement and lift.
It seems plausible that the spirol pin for the pump (rear) has sheared. Just because you can turn it by hand doesn't mean it isn't broken. The "ragged ends" of the broken spirol pin may be causing enough resistance that it seems OK moving by hand but may be slipping under engine power.
You need to look underneath to see if the shock of dropping broke any other parts. Check all the pivots where the hydro lever moves the linkage.
EDIT
Adam's suggestion below is spot on.
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