It seems Wahoo is no longer returning those Zwift rides from its API. I am going to try contact them about it. The “workout_summary” field here would normally be an object with the file to download etc…
{
"workouts": [
{
"id": 356790744,
"starts": "2025-04-26T13:28:11.000Z",
"minutes": 48,
"name": "Virtual Cycling",
"plan_id": null,
"route_id": null,
"workout_token": "FID1338 426F936B:0",
"workout_type_id": 68,
"day_code": null,
"workout_summary": null,
"fitness_app_id": 1338,
"created_at": "2025-04-26T14:16:26.000Z",
"updated_at": "2025-04-26T14:16:26.000Z"
},
Edit: I have logged a ticket with Wahoo.