would it know if engine 2 fire push button has been pushed to closed x bleed ?
It's not that smart.
Despite any fire push button been pushed, the X Bleed valve will open when you introduce APU bleed air. You have to select the X bleed valve closed before opening APU bleed valve (in anticipation - Avoid) or subsequently when you observe the X bleed valve has opened when you look at the pneumatics page (reactionary - Trap).