2015 isx15 loosing coolant

[Mfrazier6454]

I have been loosing about a gallon of coolant a day. Pressure tested the system found 2 small external leaks and took oil pan off no loss out of the bottom. We took the cross over pipe off and it had clear condensation in it as well did the back pipe on the EGR cooler. Today we found coolant in the crank case filter and sludge. The oil and pan are clean of moisture. So we don't know if it's the cooler or a head gasket please help