It is always worth remembering that the point of cross-examination is to convince the tribunal.
Often people get confused about this. Often they seem to think that the point of cross-examination is to break down the witness and make him accept that he is wrong or lying.
This never happens.
Or to be more accurate, it so rarely happens, that it is not a worthwhile objective. Human nature being what it is, people are reluctant to admit that they are wrong and even more reluctant to admit they have lied. This is especially true when they are in a public, potentially embarrassing situation, such as a tribunal hearing.
In practice therefore, even when a witness is confronted with cast-iron evidence, they are unlikely to radically change their story.
This, however, doesn’t matter very much. Your aim should be to get whatever useful admissions you can and confront the witness with the evidence. If the evidence is strong, whether they accept it is largely irrelevant. The tribunal will see that their answers are inadequate and unconvincing.
Once this has been done trying to make the witness give up and accept your account of events is unlikely to work. It is more likely to waste time and obscure the point you are making.
Always remember that it is what the tribunal thinks that matters.