Hello. In a couple months my family and I will be flying out of Miami. My wife and two of my daughters are flying on American back home. I will be on United because I got my ticket on miles. My wife has traveled quite a bit, but isn't very familiar with getting around big airports and she has never flown out of MIA. I am very familiar with the Term D and E side of MIA, so I was planning on going with her first so I could get her and the girls to their gate and then head to my gate in G. (united) This would make me more comfortable because I'll know that they're not lost or late or whatever.

Here's the question. Seeing as I will have a United boarding pass, will I be able to enter the south terminal security checkpoint? Secondly, can I get all the way from D to G without exiting the secure area?

On another note, MIAs website says united is actually operating out of H, which I understand to be a nicer concourse than G. However, all of United's information says they are located in G. I hear G is like the oldest concourse and hasn't been updated since the 60s or something. How bad is it? I'm not expecting DFW Terminal D, but it would be nice if I didn't have to wait 3 hours in the slum.

Thanks!