Heavy white smoke

So basically i have:CA18DET, decat, some hybrid t25, i think its some ballbearing one(didnt took it apart) no chip and rebuild engine like 40k kms ago ?

basically during summer i had a big leak from oil return(turbo to pan) it sprayed oil all over etc, drove with it a decent amount(ye ik i shouldnt but it was daily) since i was waiting for parts.

It got fixed but headers on turbo blew, it was welded before by previous owner so we replaced it with aftermarket and had to do some changes, while turbo was out we checked for play and there was almost none, then gasket glew on turbo since it was solid exhaust from block all the way to the tip, we added flex element and redid the whole gaskets again, after that the turbo started to make a lot of white smoke and you can smell oil in it also, its worst on idle, mostly when it warms up, im chipping the ecu soon to stage 2 since i have all other components except T28 so im gonna try it with my hybrid, question is, its impropable that some gasket inside of engine blew ? since its "freshly" rebuild or it is most likely the turbo some inside gasket blew from previous oil leak ? also was thinking if maybe its combination of decat in winter and some oil left overs in exhaust from the leak ? would like to get some feedback from you guys!

is the intercooler pipework full of oil?

Did not checked the intercooler tbh, you think it might be pulling oil from intercooler tru engine ? wouldnt that mean more smoke on higher rpms ?

It's most likely the turbo.

Gonna strip the turbo then and see how it looks on the inside, if its only gaskets or if something else is damaged, like there was almost to none shaft play, from that gonna see if i need to get t28 or if i can save this(if its actually ballbearing

Ball bearing has no parts to replace, you just get a new housing unit.

Turbo's can leak with no play in them.

Thing is idk if its ball or journal. There was not none but close to none, you can barely feel it, already got my hands on gtir t28 so gonna fit that in and take apart this one and see if thats the problem and what the problem is, since i heard the gtirs t28 is laggy, spooling after 4k rpm on ca18det, if it will be too laggy then ill just try to upgrade this turbo and fit it in, also gonna take apart the whole intercooler piping and check the pvc system