ReadProcessMemory not working with Dolphin emulator

Question

I'm trying to get access to some of the values in the memory of an emulation of Smash Bros Melee running in Dolphin. The Dolphin debug mode says that the address of the value I want is 0x80C6BA10 (I'm assuming that it means 0x00C6BA10, because 0x80C6BA10 goes over the integer limit, and it had previously referred to the same address as 0x00C6BA10). But when I pass this into the ReadProcessMemory function, I get a byte array that is just [0,0,0,0] (I'm using 4 bytes because the value I'm trying to get is an 8 digit hexadecimal number).

I tried to use OllyDbg to check if the address is right, but for some reason Dolphin doesn't work with OllyDbg, maybe because it isn't 64 bit? I've also tried using the unchecked() method in order to pass 0x80C6BA10 instead of 0x00C6BA10.

public class Program
{

     //Constant that says we want to just read memory
     const int PROCESS_WM_READ = 0x0010;


     // **** Imports the functions used to get memory data ****

     [DllImport("kernel32.dll")]
     public static extern IntPtr OpenProcess(int dwDesiredAccess, bool 
     bInheritHandle, int dwProcessId);

     [DllImport("kernel32.dll")]
     public static extern bool ReadProcessMemory(int hProcess, int 
     lpBaseAddress, byte[] lpBuffer, int dwSize, ref int lpNumberOfBytesRead);


     static void Main(string[] args)
     {

         //Gets process by finding the first process with the name dolphin
         Process melee = Process.GetProcessesByName("Dolphin")[0];

         IntPtr processHandle = OpenProcess(PROCESS_WM_READ, false, 
         melee.Id);

         int bytesRead = 0;
         //The list that will be populated by the data we find in the 
           memory
         byte[] buffer = new byte[4];

         //Reads the memory at the specified location
         ReadProcessMemory((int)processHandle, 0x00C6BA10, buffer, 
         buffer.Length, ref bytesRead);

         //Converts byte array into floating point number -- not currently 
           being used
         float memoryValue = BitConverter.ToSingle(buffer, 0);

         foreach (byte b in buffer)
         {
             Console.WriteLine(b);
         }

         Console.ReadLine();
    }
}

I expect the output to be anything but 0, but what I get back is an array of 0s. I think part of the issue might be that I'm trying to get memory values from a process that is running as a sub-process of Dolphin.