Agreed, the only disaster situations I can think of where an airship might have use are earthquake and war zones, which are often hard to reach by vehicle or plane, and may have calm enough weather to support an airship.
They'd be great at secondary recovery once they get into place but they're so slow you can't use them for the immediate recovery and life saving efforts unless they're immediately in the area.
Yeah basically only useful as cargo lift and maybe as mobile medical facilities.
They could maybe act like mini versions of the hospital ships run by the US and others for inland areas beyond the reach of ship based care. Still kind of runs into the response speed issue. In the time it takes a blimp to trundle over from wherever it's stored helicopters can deploy a lot of materiel.
A Zeppelin NT can reach up to 125 km/h, that's way faster than any truck can possibly reach in a disaster zone. The only thing faster and as versatile is a select breed of cargo choppers like the Mi-26 (Russia) and the CH-53K (US), but flying choppers comes with risks on its own from rotor downwash.