The only real difference I see is that I removed the commandclass = 91 section from my lzw31-sn.xml file, and you commented it out. That should cause this issue though.
Even though it gives you an error in your logs, does it post anything to MQTT when you try to trigger a scene?
zwave/19/91/1/1 {"value_id":"19-91-1-1","node_id":19,"class_id":91,"type":"list","genre":"user","instance":1,"index":1,"label":"Scene 1","units":"","help":"","read_only":true,"write_only":false,"min":0,"max":0,"is_polled":false,"values":["Inactive","Pressed 1 Time","Key Released","Key Held down","Pressed 2 Times","Pressed 3 Times","Pressed 4 Times","Pressed 5 Times"],"value":"Inactive","lastUpdate":1585858873270}
zwave/19/91/1/1 {"value_id":"19-91-1-1","node_id":19,"class_id":91,"type":"list","genre":"user","instance":1,"index":1,"label":"Scene 1","units":"","help":"","read_only":true,"write_only":false,"min":0,"max":0,"is_polled":false,"values":["Inactive","Pressed 1 Time","Key Released","Key Held down","Pressed 2 Times","Pressed 3 Times","Pressed 4 Times","Pressed 5 Times"],"value":"Pressed 1 Time","lastUpdate":1585874859473}
zwave/19/91/1/1 {"value_id":"19-91-1-1","node_id":19,"class_id":91,"type":"list","genre":"user","instance":1,"index":1,"label":"Scene 1","units":"","help":"","read_only":true,"write_only":false,"min":0,"max":0,"is_polled":false,"values":["Inactive","Pressed 1 Time","Key Released","Key Held down","Pressed 2 Times","Pressed 3 Times","Pressed 4 Times","Pressed 5 Times"],"value":"Inactive","lastUpdate":1585874860473}
zwave/19/91/1/1 {"value_id":"19-91-1-1","node_id":19,"class_id":91,"type":"list","genre":"user","instance":1,"index":1,"label":"Scene 1","units":"","help":"","read_only":true,"write_only":false,"min":0,"max":0,"is_polled":false,"values":["Inactive","Pressed 1 Time","Key Released","Key Held down","Pressed 2 Times","Pressed 3 Times","Pressed 4 Times","Pressed 5 Times"],"value":"Pressed 2 Times","lastUpdate":1585874863804}
zwave/19/91/1/1 {"value_id":"19-91-1-1","node_id":19,"class_id":91,"type":"list","genre":"user","instance":1,"index":1,"label":"Scene 1","units":"","help":"","read_only":true,"write_only":false,"min":0,"max":0,"is_polled":false,"values":["Inactive","Pressed 1 Time","Key Released","Key Held down","Pressed 2 Times","Pressed 3 Times","Pressed 4 Times","Pressed 5 Times"],"value":"Inactive","lastUpdate":1585874864804}
Scenes are automatically set back to “Inactive” 1 second after being triggered by default