Try smth like this, to convert response object to TyjJSResponse format:
var responseObject = {
Body: usableResponse.Body,
Code: usableResponse.Code,
Headers: {}
}
for (var k in usableResponse.Headers) {
if (usableResponse.Headers.hasOwnProperty(k)) {
responseObject.Headers[k] = usableResponse.Headers[k]
}
}
return TykJsResponse(responseObject, {})