Anything else changed besides your Alteryx version / Tableau Output version? Seems odd. Have you also raised a support ticket?
Yes, the same issue here. Works the best just ONE output in ONE workflow, but as soon as you try to add additional connection it fails.
In addition to the mentioned error, I got also:
Has anyone had any luck solving this? I have the same error: "Expecting value: line 1 column 1 (char 0)".
Yes, it depends what you are using in the workflow >
This error usually appears if you have more than 1 outputs in your workflow. By using the "Block Until Done" tool - you will allow to the server establish the "handshake" properly and the error would be resolved. Tested with 30 + output in one workflow. Just make sure they executed in sequence