Only the High Pressure EGR cooler( one on the top) cracks due to the flex connections, and the high pressure, high temp gasses that go thru. The Low Pressure EGR cooler is exposed to much less harsh conditions and temp changes and i never heard of one cracked.
After I have removed and re-installed the EGR safe mode is kicking at low to medium load. I was towing the boat the other day and when cruising @65 mph all was good. The moment I get to a slight uphill the safe mode kicks in. It is great fun to restart the car when losing speed at a busy highway highly populated with trucks (I5) If I am going full throttle, no problem. I am afraid now the bottom pipe of the cooler cracked, but I dont see any signs of soot and cannot feel any smell. It may be a time for a closer inspection.