Update: On my last round of messages with SM support they agreed to send me a new laser head and controller under warranty. They sent me “diagnostic” firmware to try, which basically re-directs the toolhead to the Add-on1 port. Under this port the filament feed stepper does function, confirming that the controller got damaged along with the laser. An advantage to this is that now I can use the 3D print head under the re-directed firmware while waiting for the new modules.
So I had to push a bit, but the company is honoring the warranty. They must be losing significant money over this poor connector design (and I suppose I must have plugged the laser head in backwards). That’s too bad. The fit and finish of the machine is otherwise impressive. I look forward to further exploring its capabilities.