Speech to text conversion is not a pure Python solution. It must be based on some kind of "external service". From the details you have provided, it looks like some web service.
Yes, you are right. It's based on IBM Watson's web/cloud service. Your error occurs because what the "external service" has delivered it not what "speech-to-text" has expected. More precisely, "speech-to-text" has excepted as result a dict with a "results" key -- but this is missing (likely because some input is wrong or there is a version mismatch between your "speech-to-text" and the "external service"). Someone else also thought there is a version mismatch between the "speech-to-text" and the "external service". The external service has been update four times since the "speech-to-text" library was put together. I expect that the "data" mentioned in the traceback above contains some clues for what went wrong. I would use the Python debugger to investigate along these lines. As you are not yourself a Python programmer, find one in your region to support you. Could someone kindly advise how to use "the Python debugger"? -- https://mail.python.org/mailman/listinfo/python-list