SLK 230 99 WOULDN'T START
 

I had a SLK 230 1999 with 49k miles, recently had a light rear end accident. There was a little damage to the back bumper. I took it to the Cherry Hill MB body shop located on 750 Cuthbert blvd, NJ 08002. After they repainted cost me $420.00. Then they told me the car won't start. I had that problem couple wks ago. All the light in the dash board was normal. I wait around abit then it started when I turn the ignition key. So at the body shop, they had a mechanic guy came over, I guess he was sent from the Cherry Hill MB dealership. They told me the problem was the CONTROL MODULE -ABS/ASR. They replaced it then charge me $200 for that module. When I came to pick it up at the dealer, they did fixed the paint on the rear bumper. But I found out the trunk lid won't close with the top up or down and missing the panel right at the 6-disc CD changer located in the trunk. I have to leave it there again for them to refixed it. Hopefully they refixed and won't charge me again. My question is
1) was the fixing control module has to do with the missing panel located at the CD changer in the trunk?
2) why would the trunk lid wont close?
3) was the control module ABS/ASR is the culprit of car won't start when u turn the key with no cranking?
4) or the bodyshop/mechanic guy didn't do the good job?
5) any one has good/bad experience with those service at the cherry hill MB dealership? would you recommend it?
Thanks, your answers are greatly appreciated for my next experience at those places and what to prepare for.
ND