AWS::Events::Connection 'GeneralServiceException' encountered when creating via CloudFormation

I am trying to create a new stack for some EventBridge resources. I'm setting up an API destination with a Connection using OAuth credentials which will be invoked by a rule watching S3 object creations.

However, I keep getting an error on the creation of the Connection construct (AWS::Events::Connection).

Resource handler returned message: "Error occurred during operation 'AWS::Events::Connection'." (RequestToken: [REDACTED], HandlerErrorCode: GeneralServiceException)

The code below was deployed successfully only after I manually created a Connection in AWS Console and then imported it in my stack. Ideally, I would manage this Connection through the stack.

Edit: To clarify, I altered the code below to import the manually created Connection and that worked as expected.

What might I be missing? How can I investigate the root cause of the GeneralServiceException? I believe I am deploying the stack with a role that has access to all actions on all resources.

const connection = new Connection(this, 'Connection', {
  authorization: Authorization.oauth({
    httpMethod: HttpMethod.POST,
    clientId: props.clientId,
    clientSecret: props.clientSecret,
    authorizationEndpoint: props.authorizationEndpoint,
  }),
});

const destination = new ApiDestination(this, 'ApiDestination', {
  httpMethod: HttpMethod.POST,
  endpoint: props.endpoint,
  connection,
});

const rule = new Rule(this, 'Rule', {
  eventPattern: {
    source: ['aws.s3'],
    detailType: ['Object Created'],
    detail: {
      bucket: {
        name: [props.bucketName],
      },
    },
  },
  targets: [new targets.ApiDestination(destination)],
});