Trying to find a new angle on possible directions. Went back to some of the searches by TC prior to the disappearance and see what he was looking at. Used the "age of consent" search in Google
(Don't turn me in I'm not planning anything just doing research tracing his possible steps, we don't know the actual websites).
There seem to be two consents, consent to marry and consent to "the birds and the bees". It's generally thought IMO that the intentions was the marry consent, but the "birds and the bees" consent rules seem to be similar in each state with an age exception which doesn't apply here.
This may lead to where it would be the most desired to go is if this was the plan.
Age of consent to marry -
http://family.findlaw.com/marriage/state-by-state-marriage-age-of-consent-laws.html
Alabama - 16, 14 with parental consent
Arizona - 18, 16 with parental consent
California - 18, or any age with parental consent
Nevada - 16 or younger with parental consent
New Mexico 17, 16 with parental consent,
Oklahoma - 16, parental consent for younger
Texas - 17, parental and judical consent for younger
Tennessee - 18, 16 with parental consent
Utah 18, younger parental consent
She will be 16 next month.
None of this means he can follow the law. He cannot legally marry her now or provide parental consent.
But if following the results -
Alabama, Nevada and Oklahoma show up as the first ones.
New Mexico, Texas are a push
Arizona, California, Tennessee and Utah are the least options.
There are some exceptions in the case of pregnancy that will change these results.