I changed the VBA code to the following.
MyRequest.SetRequestHeader "Content-Type", "application/json"
MyRequest.SetRequestHeader "Accept", "application/json"
MyRequest.SetRequestHeader "Authorization", "Token " + Base64Encode("<My API Key>")
' Send Request. HR_Automation
Going to SetRequestHeader from SetCredentials has now gotten me to an error of "invalid Credentials". I believe that this is an improvement.
***** My research has shown that the key may need to be base 64 encoded. I have tried it with the encoding, without the encodeing, with and without the "<>" around the API key.
***** Any suggestions on what I should try next? I know I'm close