DD15 / Coolant-Oil / Turbo / blow by problem

2012 DD15 800k miles
Truck ran fine until 797k miles, then DPF problems began causing the Filters to be blocked or clogged, did couple of forced Regen a , ran ok but while heavy lots of black smoke coming out and power loss while turbo fluctuations at around 1400&1500 rpm

I "fixed" the DPF/SCR problem to run "old school" style.

After about 300 miles, CEL and shutdown lights. Coolant low and bunch of smoke from breather crankcase separator with oil present and blow-by from oil fill cup and dip stick.

Refilled with water got back to the shop, replaced breather system , no change. Truck loses oil and coolant every 250 miles it seems, smokes light blue at start up and when you WOT while parked.

EGR cooler replaced 168k miles ago.

Took off hot cross over pipe and it's dry but intake side and turbo side CAC pipes have oil in them and a good amount. I'm totally lost on what's the main culprit ? Blocked EGR valve from Clogged DPF running days that caused turbo failure ( but turbo spools and seems to be working) but on the other side , would it cause the excessive Blow-by. Head gasket ? Liner ?

It takes approx same amount of coolant and oil but no visible outside leaks besides the one from Oil Breather Separator ?

While going to NJ. Got a code
2631/1 Insufficient Air Flow

cel was out in the morning and that's when I took apart piping and noticed oil in them.

I have a good friend mechanic that works on trucks for living but he is gone for next 2 weeks. Just trying to get ideas on where to start ? Turbo side ? Or head removal first ?

 

Also I should add, looks like coolant is not going into an oil because it's not milky on the dipstick and oil cap has minimal residue which might be from a blow by steam and vice versa for a coolant expansion tank.

 

Sold the truck to local mechanic, he took it apart. Cyl 3 cracked liner and blown Turbo. Sold it for 7k.

I was running for couple of weeks with what seemed to be clogged DPF filters then did a delete and within 200 miles after issue appeared. Most likely truck ran way too hott stressing Turbo n CYL head.