I agree. They are probably just using this exit by MM to scout around for a new recast. Think of the possibilities if it wasn't Adam that actually hit Delia.?
1) Adam gets tried and convicted, Chelsea divorces him and maybe, even just maybe gets close to Jack? Then, when Adam is found innocent, or man, watch the fireworks when he heads back to town!
2) Gives Victor the perfect opportunity to get his hands on poor Conner!
3) Kelly turns out to be the culprit and man won't Billy Boy feel like crap then!
I really think it's Kelly and the con holds the key. I think he is going to tell Alex that he saw a 'woman' at the wheel, not a man. The writers may just be playing cat and mouse with us about this, much like they did the Stitch/Dylan thing.