2007 e550 misfires

Mercedes » E-Class » 2003-2009
Problem Description

About a month ago my check engine light came on while driving down there he freeway. When I cam to the next stop it began to studder a little bit. I took it to the local European shop in my area that Is known to be ( besides the dealer)who to go to. They first told me after diagnosis the vehicle needed a coil pack on cylinder 5. After being gone a week I called and they said the misfire had moved to cylinder 2 and that also needed a coil pack. I said ok and figured that was that. When I didn’t recieve a come pick up your car call after 3 days I called them and they said the car had low compression in all cylinders now, they couldn’t figure out the problem and to come pick up the car. I am frustrated and can’t understand why it has low compression now and it runs the same as it did when I dropped it off. Has anyone heard of these misfires jumping or the compression problem at all? Please help