Perhaps. You're basically upset at your bank that another bank didn't transfer over funds that said they would. So they (united) calls the other bank on your behalf and that bank (air china) says "I don't know who they are, we can't help you". Then you're upset that your bank doesn't have any more information.

Also, keep your boarding pass. It will really help in situations like this next time. Did United know you were on a group tour? The operating airline is always the party you have to sort this out with in a scenario like this.