If you make a prediction correctly, and it is ignored, then that's an indication that you should either make it more assertively next time, or you just can't work with this person.
And anyway, some humbleness is due -- sometimes we think we've given good advice, but it ends up being somehow inapplicable to the problem for reasons that are outside our scope.
Maybe therein lies the rub (a fun idiom): if one wants to say "I told you so", or whichever variant to say "I was right", then one should also say "I did not tell you so", or the "I was wrong" when that person made an incorrect prediction :-D
If you make a prediction correctly, and it is ignored, then that's an indication that you should either make it more assertively next time, or you just can't work with this person.
And anyway, some humbleness is due -- sometimes we think we've given good advice, but it ends up being somehow inapplicable to the problem for reasons that are outside our scope.