Hey 
Bubble’s support team required a test workflow, which wasn’t easy to provide since it was using a webhook triggered by Stripe itself…
So instead I provided a workflow retrieving the invoice ID via two different methods (via a custom API call and via Bubble’s plugin) to demonstrate the bug. This was in itself a workaround. And since that workaround works, Bubble didn’t think it was worth investigating further (they have to prioritise our numerous requests 
).
The demonstration:
The result of the demonstration in the database:
The custom API call to retrieve the Event:
Then the invoice ID is the Event’s Object ID:
I’m still using this to date. Works fine 