> They can lie, but if they say they did and it crashes on me right when I start it, then I may never trust this contributor ever again.

If it’s obvious without a shadow of a doubt that someone has lied, either on an issue or a PR, I’m very much inclined to block them. I have a lot of patience for people who are still learning or make silly mistakes but are genuinely making an effort; but if someone doesn’t even help me help them, that’s disrespectful and such behaviour shouldn’t be rewarded.