I contact American Express about this concern and they said that if they do bankrupt I can dispute this charge
That sounds a little questionable to me.
I am not an attorney, but based on my understanding, at least in the US, if you paid a company for something, and before they provided it to you they filed for bankruptcy, their obligation to you becomes part of the bankruptcy filing. I am not so sure it can be refunded without court approval (at least of the general terms of the bankruptcy, providing guidelines for things like this).