Do u know of the reason why it cracked? Due to hot, cold, age, etc...

Do u why it cracked? Hot, cold, age, etc....

For it to be pressuring up the coolant it has to be leaking from the combustion area.
You say the head gaskets look good so it is either a cracked head or cylinder wall.
Pull the plugs and look for moisture or rust on one (or more), and that will tell you which cylinders to scrutinize.
My guess is a cracked head between the valve seats.
Running hot will do it.