Throwing a P0101 MAF, stumped

I put 3 sensors in, didn't fix it. Local tdi guy is stumped. As a last resort took it to stealership, they said they found a boost leak and replaced the plastic tube(big waste of money) didn't fix it. Never saw a boost leak before.
It runs fine with no symptoms.
I've monitored the maf output while it threw the code, no spikes in voltage.
Kind of at a loss, could it be the turbo?

Smoke test it. I stick the tester in the breather tube from the valve cover, take the air inlet tube off at the MAF housing and plug it off, and plug off both tailpipes by stuffing rags in them.

Then turn the smoke machine on. If there are any leaks, it'll eventually show up. But it obviously does not put out the same pressure as what would be present under boost. But I have found lots of leaks this way. This will also test for "false air" leaks between the MAF and the turbo inlet.

You can also check to make sure the EGR valve is totally shut, too.

If you do get to the "check your EGR" phase, my suggestion would be to not just look at it to see if it's closed tight. Use the output test in VCDS to actually make it move while you watch.

I say this because we recently chased a stubborn MAF code for months, having convinced ourselves the EGR was not the issue by looking at it statically.

Oilhammer suggested the output test, and sure enough... once we saw it move we could tell it was only closing fully once in a while. Shining a flashlight thru it made it clear that it was seating a bit sideways three times out of four.

New EGR, MAF code gone.

I've got the p0101 code, can't seem to find the cause, egr delete with Malone 1.5 tune, changed maf and map sensors, changed the o=rings on the intake tract, runs fine with the code, usually sets when you are cruising and encounter traffic, and let off to coast, wondering now if it could be a vacuum problem, boost pressure seems low, 900 called for, 835 actual when idling, boost catches up as rpm increase, have driven 100+ miles without the code but it usually happens at idle could it be a vacuum problem, either a leak or tandem pump? With the egr delete it has hit 53mpg!