You dont have to waste money on new EGR.Have the vaccum test ythe solenoid by the mechanic to see if holds vacuum.If it doesnt ,no problem,what you do is ask the mechanic to block to vac pipe that goes to solenoid (he will need to look under manifold) .If the solenoid holds vaccuum (reading should be 350-450 HG)Then you can simply just block the vac pipe that goes to EGR valve,(use a small bearing on the vac pipe on the valve itself).
Just do it in a way that you can connect it in future for diagnostics.

The blue tint smoke ,you can do a simple test!
On normally aspirated cars it would be valve or piston rings,but on turbocharged cars cars you have the turbo.To eliminate being the turbo seals,you need to disconnect the breather pipe that goes from the vortex filter you fitted and the air pipe on turbo!You have no problem leaving it disconnected for testing as this only breathes out!I want you to warm car up or drive for 5-10 mins and then stop car and leave it a few hours and then start it and see if you still get smoke!If you do ,its turbo seals ,since you disconncted engine breather!

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2003 BMW X5 E53 3.0D-Auto, Sportpack,full extras.
Oxford green/Leder Dakota interior.
56, 875miles @24th October 2024
Heavily OE modded,including full facelift grill install.4.6is body kit,wheels,exhaust tips and ext.fender flares
Non OE mods.Depo "custom" Angel eye headlights.