New turbo

What's in front of the turbo? An engine. A slobbering cylinder can cause you to see oil or fuel on the turbo too. You'd likely have other symptoms too though if that was the case. A usual tell-tale would be dampness at one of the gaskets between the head an exhaust manifold.

 

You can check a lot of things instead of swapping parts.

 

The ones I have found restricted had a plastic cap left in them or a hose involved.
One was an F model Mack with a Cummins. I was sent on a service call. When started it put a white cloud in the sky. Found a phone and called the commander. Answered the questions. He said the turbo seals are bad. Bring it back and rebuild it. Yes sir.
Rebuilt the VT50 turbo and put it back on. Same problem and I called back in. I was told " You did something wrong. Take it off and bring it back in".
I did not thank I did anything wrong and went snooping. The return line on those had a flexable orange hose in the middle. The outside looked normal but ends up it was a silicone hose. A pencil would not have went through the center of the 3/4" ID hose.
Spied a junk hard garden hose on site and we were all down the road.
Know I am dated but why I mentioned those things to check. Checking is usually a lot less expensive than swapping parts. Hope you got that all worked out.