My struggles with the travelers checks

I don't have a picture that relates to the topic, so this is a beautiful lake in INBio.

Don't get me wrong. I'm having a wonderful time here in Costa Rica, but its becoming SO stressful having to deal with the travelers checks.
I expected them to be able to work here in C.R. but because my signature has changed so drastically since I was 14, the signature on my passport and on the checks is very very different. I've been to literally 5 banks and we've called American Express 3 times (thank you Crista and Basia for all of your help!) and we didn't have any luck until today.
Basia went before me and argued with the teller at Scotiabank for half an hour until the teller agreed to call American Express and ask if they could take the checks. After the call the Scotiabank FINALLY agreed to see my checks. The only problem now is that my signatures are slightly different on each check!!! I could only cash one and I have 4 more that need to be cashed. This is becoming a huge stress-er and a huge hassle. But I at least got one cashed for now, and that'll be okay for the next few days.