2021 Cascadia DD15 - need help with coolant leak

Hi all, anyone have any idea what else to look for or where the leak is coming from? Did the pressure test, nothing leaking. While truck is idling even with AC on high, still no leaks. Seems to only happen when under heavy load/uphill, or at least that’s when I notice the smell. I checked all the hoses, even the compressor one that goes to the front, re-tightened bolts and clamps, but the leak is still there, 1gal every 400 miles or so give or take.

I know there’s a piece that can leak behind the fuel filter housing, but figured it’s worth to see if anyone has any ideas before I start taking it apart? The leak seems to be coming somewhere near the engine block where the above mentioned fuel filter housing is. Thank you!