Yes of course it's pretty safe. I never heard any political issues related to terrorism in Aruba. Moreover, it's a small island which is likely easier to take care of than a big island or continental area.
I have never heard about political issues in Aruba. Terrorists are usually trying to make some type of political statement. Perhaps if there were someone of importance traveling to Aruba on your flight there might be a chance some terrorist would find out.
I don't know how you can be extra careful. It seems like they make threats and nothing happens or something happens somewhere else or they don't threat they just act. Does she have a friend in the CIA or special info?
