I've never been in a situation where I had to get them reimbursed on the island but I believe someone else did here on ttol and mentioned an amex office near Pburg. Whether it's still there; no clue. Worse case, I can reimburse them back home but I'm not out any money.

I would never use any single source whether it be cash, tcs, atms or credit cards as my sole access to funds.