Yes ,you can disconnect the MAF now and test.This is just to see if the MAF has a problem.Upon disconnecting ,the MAF ,the ECU will obviously not find it and it will reset engine parametres to default.So if the car is better ,then you know its the MAF.

Perform the injector test again and write down the values,to see if one is worst than others and this will be the one that you need to remove ,check and clean and if you not confident ,remove the injectors yourself and take them to a place that you mentioned .
The injectors can also be cleaned by you .Those high parameter numbers are the small orifices at the end of the injetor that get blocked and they just need cleaning with a wire brush .My injector number 4 was visibly blocked at +6 parametre!What it was doing was dripping rather jetting!
The other side of the injectors that can go wrong are the "o"rings on top which will also drip diesel to cylinder but really only on high mileage cars.

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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.