PLEASE HELP! P0237 & P2463 Error Codes

[Holyguaka]

Hello, I have had my OM651 2.1L W204 parked up for the last 2 months, trying to figure out what's causing my car to go into limp mode constantly. After driving it one day and experiencing a complete loss of power, I received an Air Intake Leak error and Turbocharger error, which persists as the P0237 error.
Initially, it only said air intake leak and turbocharger underboost. Here's everything I've done to try fix it:

1. Replace fuel filter (this was before diagnostics).
2. Checked the 3 air sensor voltages leading to/from MAF.
3. Checked the turbo & turbo actuator.
4. Checked intercooler pipes.
5. Replaced MAF.
6. Replaced Air Intake Manifold & De-Carboned the EGR intake (This thankfully got rid of the air intake leak code, but then threw the P2463 code). *I had to drive the car whilst in limp as there's no other transport locally. So I figured I clogged the DPF.

== P2463 (DPF) Fixing ==

7. Attempted a 4-hour motorway passive regen.
8. Used a DPF spray-in cleaner.
9. Removed & fully cleaned the DPF in a Wynns DPF Cleaner soak.

The car previously would creep its revs up to 2K. Since fixing the air intake leak, the car has become responsive again; however, the car still won't rev above 2.5K when in drive, but will happily rev to over 3K when in park.

DPF was definitely cleared as it looks as good as new and air & water were passing through it with 0 issue after it's soak.
I just cant understand whats going on and I have absolutely no idea what's throwing my turbocharger code!
Please give some advice on where to go or what sensors to try to check next, because I'm at a loss.

 

[toteimerced]

Most common is a boost leak, usually the intercooler hoses, but you say you’ve checked them, maybe the intercooler itself is leaking.

 

[Holyguaka]

Most common is a boost leak, usually the intercooler hoses, but you say you’ve checked them, maybe the intercooler itself is leaking.

Hi, yes I did actually check them when I first was trying the sensors to see if I could get rid of the Air Intake Leak.
Would have been a much easier job if they were at fault haha. Haven't checked intercooler, but the front looks 100% and the back fan brackets are perfect.
Think I got it figured out this morning, about to post an update.

Thank you for your reply, I really do appreciate the input

 

[toteimerced]

If you haven’t cured it, smoke test might a good move next, good luck with it.