MessageBox is usefull, but no! You cannot put an image other than the ones provided into it. No problem: create a Form class to imitate the behaviour of the message box. Because it would be a class of your own design, you can do in it what you want;)
root = tkinter.Tk()
buttons=[i for i in range(10)]
#If specific button is pressed, output "YES"
for num in buttons: