Hi Mary! Welcome to FT.

I'm sorry that things are the way they are at the moment and if air travel is a necessity, and the best you can do is try to avoid the NoS altogether by picking a checkpoint without them (Check your airport here). If you can't avoid them and still need to travel, I think the best thing to do is be that mama bear -sternly, but in control. Odds are you won't get sent to the AIT, but if you do don't give them an inch.

You know your kid best, but if I was in your shoes I'd talk with them and tell them ahead of time that you will be RIGHT there (you have the right to be with him during the entire process, whether you go through the NoS or go through a patdown).

The TSA has said that it's ok to photograph and film within their checkpoints, so long as your don't slow the process down. Given that, film everything and tell them. If they object, give them a print out of their webpage and edumacate them. If they press the issue, then tell them that you're just telling them what to expect, just like they tell the subjects of their pat downs what to expect. Be sure to pick an angle where no screens are visible, otherwise they might try to stop you or make you delete it. You might need the dad or yourself to go through first in order to be cleared before your kid and have them get your stuff (and the camera) before letting your kid go through.

That's what I'd do, but I hope that you don't have to make those choices.