I just found on my 2003 Discovery there is a hole next to the flywheel inspection hole after I removed the rubber plug. Does anybody know what that hole is for or if that something broken on the case?

 

It's for access to torque convertor bolts, when removing engine or trans.

 

Not the big round hole which was covered with the rubber plug, but the irregular shape hole right beside the big one on the wall. pls see the second picture for details.

 

Bolt for the oil pan runs through there.

 

Totally normal, faked me out too.