Adaptive headlight malfunction passenger side

[Dio781]

Hi everyone, so I got a 2016 535i with Adaptive headlight led and not long ago I had a body shop install a M5 replica front bumper 
3 weeks later my headlight got moisture built up inside 
So taking the bumper off to check the headlight 
I notice that they must've lost one the original screws the that goes on the top and replaced it a generic hex head one but the screw was longer than the original and put a hole on the headlight allowing water to get in 
And of course they are denying doing that 

I can replace the headlight myself but how complicated is Esys for coding the module 
Is that something that someone can help me with 
I do have ista which I use pretty well and Esys but never got around messing much 
But would love to get more familiarized with it 
So I can do some coding myself 

Thank you everyone