UI is only supposed to present the most updated version of the underlying data and if it makes a false request to the server using outdated data or attempting to cheat then the server verification step should catch that and drop the request with or without a notification to the player.
In other words Widgets primary job is to present replicated data in a pretty way and forward the input from the user to the server in this case. Widgets should never be the source of truth it is just a messenger.