Is that not chip and signature though? Thats what I have to ensure any fraud is not my liability :-) I just tell em I'm dyslexic and they have to issue one - they hate doing it though!
The problem is the US credit cards have no chip at all which means they cant be read by the readers at all, as far as I know - my friend had this problem when she visited last year.
Yours (and the cards issued in the UK to people who can't use a PIN) may be "chip and signature" - we don't come across them very often. USA cards do just have a stripe, but that
can be read by the readers (swiped) and it will dial through to the authorising centre in what is, I think, the same way. Then ask for a signature. We're very used to them in our line of business, and I would expect Bob to find them accepted for his group as easily as a chipped card in almost any place that they go that's on the regular tourist / visitor trail.