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Sadly anecdotes speak louder than advice, even when they are obviously unverifiable.
This could work.
Truth is people don't like being told what to do, especially by complete strangers, I know I don't. All you can really do is calmly offer your advice and not get drawn into an argument when it is rejected. Hopefully, if they survive, they will think it over later and realise it's value.
Sadly anecdotes speak louder than advice, even when they are obviously unverifiable.