Shifting cargo ? Well, that's a killer !
I don't think that any manufacturer has ever published a procedure for that kind of problem. If it happens, the only way the cargo can go is rearward, then your plane would be pitching up and if you're lucky you might regain control with the elevators (and trim). And if you manage to put your plane in a nose-down attitude your cargo might shift back to where it was, who knows ?
That guy in the DHC-8 is a lucky bastard !
I guess he used mostly the engines to change is vertical velocity and bring back the plane. BTW I heard that, in the wake of the UAL DC10 crash in Sioux City, NASA developped a software to be coupled to the auto-throttles in case of total hydraulic failure.
Do you remember what happened to a Fine Air DC8 that took off and crashed in MIA a few years ago ? You can find a report here (if you like):