Connecting Arduino to a Casio Keyboard's buttons

I am working on a project where i want to update my Casio Ca-110 Keyboard to have an LCD display to show what Tone and Beats are set. So i need the Arduino to interface with the Number buttons, Tone Select and Beat Select buttons. I have mapped out the buttons to find which pins are shared for all the buttons. The idea was to use the Keypad Library to program the Arduino. Problem is it doesn’t want to work. After setting up the sketch i run it and connect a wire from one of the Row pins to one of the Column pins but the Arduino doesn’t register the connection.

#include <Keypad.h>

const byte ROWS = 2; //four rows
const byte COLS = 6; //three columns
char keys[ROWS][COLS] = {
  {'0','2','4','6','8','T'},
  {'1','3','5','7','9','B'}
};
byte rowPins[ROWS] = {12, 13}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {11, 10, 9, 8, 7, 6}; //connect to the column pinouts of the keypad

Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

void setup(){
  Serial.begin(9600);
}
  
void loop(){
  char key = keypad.getKey();
  
  if (key){
    Serial.println(key);
  }
}

So i’m wondering if there is some other electronics on your typical key pad that i’m missing? If so will i even be able to implement this on an existing setup like the Keyboard? If i can’t use the keypad library how would i go about connecting the buttons through 2 pins on the arduino so it can detect the button press, without having to set pins high or low for fear of messing with the keyboard recognizing the button push?

This all seemed so much simpler when i was planning it in my head.

Doesn't look like my idea will work. I did some testing. If any of the pins as set high or brought high by a key press the keyboard sees that as additional button presses and things go a bit wonky. SO there is no way to get the ardino to read a key press without interfering with the keyboard. Oh well. now to find a new project.