how do I diagnose frame damage on '59 18-footer

[CindyH]

Hi,
I'm traveling in Mexico with my 1959 Airstream. It was rear-ended and the result is a really bent-in rear bumper. There was other damage, but I'm primarily concerned about the frame. An insurance adjuster will be here shortly, and I need to know where/how he should check for frame damage.

I want to acertain whether I can finish my trip in Mexico and get the bumper and other damage repaired in the States or whether there has been damage that I must repair before going forward.

So there is the safety question and
there is the insurance question.
I'd appreciate any quick advice before the adjuster arrives and links to any specific information about diagnosing frame damage and its repair.

thanks for your help.