Someone correct me if I'm wrong, but I think it has been pretty clearly established and publicized by LE (so that's what I'm choosing to believe) that it was in fact MH's car. An earlier poster stated that it was in the "normal" lot, which I read to be the one directly adjacent to JPJ (though whether on the lot or in the multi-story parking structure I don't know).
I don't know if DH still believes otherwise, but it wouldn't surprise me if he has changed his own mind about that, and that (in LE's/DH's mind) unimportant detail just hasn't been shared. The car doesn't seem to be LE's focus (maybe it should be, but they express that it's not), nor how she got out of the arena, but what happened after she was outside and after 9:30.
I'm in total agreeance with you. I believe based on LE media statements that it was MH's car at the arena and that dad may have been told differently by her friends. Because of insurance purposes I made my kids swear to me they wouldn't ever let anyone drive their vehicles, because I was liable. I also told them if they weren't able to drive (for whatever reason) they should call me for a ride, no questions asked. However, if they followed my rules all the time, I'll never know. I still think MH's friends gave the truth of the matter to LE after they told her dad a little fib to protect their friend. MH probably gave her keys to the DD because she wanted to imbibe never imagining her dad would find out.
Her mother stated in one of the first interviews how extremely close MH and her dad are. I can totally see MH bending his rules and yet not ever wanting to disappoint him. Heck, I used to bend my mother's rules on occassion and I had the utmost respect for her. As an adult, she has told me (when I've tried to confess a few of my younger years transgression) that there are just some things a parent doesn't want to hear from her adult children after the fact! LOL