You're conflating two things. Inflation has little do with how well a remittance system functions. You wouldn't say that Western Union's system functions better or worse because of the currency it is denominated in.
> so it seems to me that they were trying to solve a problem that existed in their countries, but not in El Salvador.
While not inflation, El Salvador doesn't have a great history of fiduciary responsibility either. [1] 1 - https://en.wikipedia.org/wiki/History_of_El_Salvador#Corrupt...