If Alonzo and Lindsey wanted to "get rid" of MJD - for whatever reason, I just cannot believe they would have just thrown her out the window on a highway where there were witnesses. This is the reason I believe MJD did jump of her own accord. Not that it's really relevent to what we're doing here.
Also, if - AND I MEAN IF - MJD was Michaela or any other child who was abducted as a young child, we can pretty much safely assume that she did not necessarily receive the best of care. That could easily explain a smaller stature or more child-like physical structure, but it could not explain the good dentals or the jewelry - IMHO. Still, I find it nearly impossible to believe we will find MJD on any of the missing persons boards. It's been 9 1/2 years FGS - it surely seems NO ONE IS LOOKING FOR HER!!! IMO - there is a reason. I think we must rely on Kelly Lipsey and/or the other girls he transported by him for prostitution. Or Robin Angers, who seems to have been the ONLY person in this story - so far - who ever gave a c--p about trying to save this little girl.