Eggtastico wrote:If your that worried - buy some crutches off ebay & tell her to put on a limp
Whilst I realise [or hope] this suggestion was tongue in cheek, as people feigning disability really make my blood boil.
It's often said the jet-bridge to an aircraft is nicknamed the "Lourdes Jetbridge" as a minority of people who insist on pre-boarding due to medical conditions at the departure airport make a miraculous recovery during the flight and are able to close on sprint to immigration on arrival.
Similarly, I used to work at a theme park in the UK. Back when I was there people could claim practically any medical condition (including deafness) as to why they were unable to queue up & got issued with ride access passes to avoid the queues for them & a helper (although in practice they gave the whole party passes). These people would avoid queues all day and get way more rides in than able-bodied people who had to queue (they also used to charge the disabled guests half price too).
Thankfully they have clamped down big-time now & you need to show a blue badge / NHS letter stating why you are unable to queue. Deafness is no longer accepted & they don't let you re-ride until you have waited the time of the current queue. They also charge disabled guests full price, but let them bring a helper for free.
Back to the OP - tell your sons' girlfriend to speak to the crew when making a toilet visit in the quiet time after the main meal service. There will be in all the galleys / sat on jump-seats nearby, I am sure they will be happy to explain the arrivals process & answer any questions she has. They will happily help her with / check her Customs declaration form if she has any queries about it, but she remains 100% responsible for the information on it, as she has to sign it.
In Immigration, if she is nervous, just tell the officer it is her first time travelling alone (don't say to the USA unless this is true, as they can see all your previous arrivals & departures on your current passport number). If her return booking is on a different e-ticket, it would be advisable to have a printout of that - just in case the officer thinks "Aah, OK, travelling on a one-wy ticket and meeting her boyfriend in the USA" - they may think you are intending to marry and overstay.
All I can say is that in 15 odd visits to Orlando, I've only had one rude immigration official. Most are very friendly and helpful. Yes, they are understaffed (blame US Austerity) and the afternoon rush mush be daily hell for them.