Coding Key difficulties with JSON, Swift 4.1

I have a JSON with a response body that appears as follows:

{
    "Count": 116,
    "Message": "Result returned successfully",
    "SearchCriteria": "Search Criteria",
    "Results": [
        {
            "Value": "",
            "ValueId": "",
            "Variable": "Suggested VIN",
            "VariableId": 142
        },
        < 115 more like this >
    ]
}

Initial Attempt

I initially attempted to create coding keys, as follows:

struct ResponseBody: Codable {
    var count: Int
    var message: String
    var searchCriteria: String
    var results: [Result]

    enum ResponseKeys: String, CodingKey {
        case count = "Count"
        case message = "Message"
        case searchCriteria = "SearchCriteria"
        case results = "Results"
    }
}

struct Result: Codable {
    var value: String?
    var valueId: String?
    var variable: String
    var variableId: Int

    enum ResultKeys: String, CodingKey {
        case value = "Value"
        case valueID = "ValueId"
        case variable = "Variable"
        case variableID = "VariableId"
    }
}

With no complaints from the compiler, I tried to decode it with this code:

// network request code
    let decoder = JSONDecoder()
    var responseData: ResponseBody?

    do {
      responseData = try decoder.decode(ResponseBody.self, from: data)
      guard let responseData = responseData else { return }
      let vehicle = self.createVehicleStruct(from: responseData)
      self.dispatchGroup.notify(queue: .main, execute: {
        completion(vehicle)
      })
    } catch {
      print(error, error.localizedDescription)
    }

which yielded this error:

keyNotFound(CodingKeys(stringValue: "count", intValue: nil), Swift.DecodingError.Context(codingPath: [], debugDescription: "No value associated with key CodingKeys(stringValue: \"count\", intValue: nil) (\"count\").", underlyingError: nil)) The data couldn’t be read because it is missing.

Working, but hideous attempt

Eager to "get on down the road", I tried the following and I was able to parse the JSON, but the non-conformance with Swift naming convention drives me batty:

struct ResponseBody: Codable {
    var Count: Int
    var Message: String
    var SearchCriteria: String
    var Results: [Result]
}

struct Result: Codable {
    var Value: String?
    var ValueId: String?
    var Variable: String
    var VariableId: Int
}

Now, I'm back to attempting to get nice, clean names in my structs now that I know the networking part works. Upon further further investigation, I needed to provide an init(from decoder:), so I refactored as follows:

struct ResponseBody: Decodable {
    var count: Int
    var message: String
    var searchCriteria: String
    var results: [Result]

    private enum CodingKeys: String, CodingKey {
        case count = "Count"
        case message = "Message"
        case searchCriteria = "SearchCriteria"
        case results = "Results"
    }

    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        let count: Int = try container.decode(Int.self, forKey: .count)
        let message: String = try container.decode(String.self, forKey: .message)
        let searchCriteria: String = try container.decode(String.self, forKey: .searchCriteria)
        let results: [Result] = try container.decode([Result].self, forKey: .results)

        // FIXME: Extra argument 'message' in call
        self.init(count: count, message: message, searchCriteria: searchCriteria, results: [results])
    }
}

struct Result: Decodable {
    var value: String?
    var valueID: String?
    var variable: String
    var variableID: Int

    private enum CodingKeys: String, CodingKey {
        case value = "Value"
        case valueID = "ValueId"
        case variable = "Variable"
        case variableID = "VariableId"
    }

    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        let value: String = try container.decode(String.self, forKey: .value)
        let valueID: String = try container.decode(String.self, forKey: .valueID)
        let variable: String = try container.decode(String.self, forKey: .variable)
        let variableID: Int = try container.decode(Int.self, forKey: .variableID)

        // FIXME: Extra argument 'valueID' in call
        self.init(value: value?, valueID: valueID?, variable: variable, variableID: variableID)
    }
}

I'm getting an error in init(from decoder:) when I call the init:

Extra argument 'valueID' in call

I can't figure out where my mistake lies. If you have suggestions, I welcome your input. Thank you for reading.