Tease.close.....
Depends..
Would it help? Would it harm? What's the balance? Can you actually prove it, or would they keep disbelieving? People are often stubborn that way.
You could try it on us?
The Novikov self-consistency principle would like to have a word with that theory. If it's going to happen, it already has. If it hasn't, it won't. What ever we would/will do with that information would/will/has/had lead to it already having become/becoming/became true....but if it's the proof of Artificial Intelligence that might send a robot in the past to kill someone at the cost of someone important, then it would be worth it because you'd actually be doing something with that information/proof.