That's a real bummer. Is there any way the author can prevent this? Can he generate random indexes that don't repeat while keeping this random number generator code public?
The only way to address this would be validating the answers server-side. Any information you leak in the locally executed code can be discovered without much effort.
I think Wordle doesn't server-side validate because of volume, and also because it's a fun little game and cheating brings you nothing of value.
