[techhelpbb]

Somewhere you've lost a line...I highlighted it red.
The line you want to add is shown in green.

            if(strcmp(buffer,"POST ") == 0)
            {
              client.find("\n\r");
              while(client.findUntil("PinD", "\n\r"))
              {
                int pin = client.parseInt();
                int val = client.parseInt();
                pinMode(pin, OUTPUT);
                digitalWrite(pin, val);
                Serial.println("I saw the POST and toggled the pin!")
              }
            }

Also I noticed you statically assigned the pin I think it best you start with the original unmodified code for this.
Just add the one green line to the original code.

Be back in 2 or so hours....gotta go to a MORT thing.....