Turned out that both switches were shot. The rod that operates the switch in the stalk was jammed/frozen, no movement at all.

Once I got the replacement part - $65 + shipping at FCP for the OEM, in the Volvo bag part - I saw what was missing on old wraparound switch, the slide fitting that keys into the lock cylinder. I found most of the missing slide in the bottom of the door frame.

Real PITA to install. Not much finger room to work, and there is a certain sequence you have to use as you reassemble the mechanisms. I found that taking the screws out of the cylinder locking plate and moving the plate about a quarter inch away from the door jamb was necessary to provide the clearance to fit the wraparound switch on the cylinder.

I guess the amazing thing here is that it took 21 years and 220,000 miles for the original electrical/mechanical part to fail. And that all of the other parts of the system, all of the actuators on the other three doors and in the trunk, are still working just fine.