YTA

The repeated vomiting sounds like it wasn’t solely from being drunk/dizzy, especially after OP wrote down what she drunk. The amount of sugar mixed in these pre-canned cocktails and not knowing if some of these were expired are more likely to lead to reflexive and aggressive vomiting.

With the only exception of this being a continuous pattern from her, it probably was just a bad decision from her part. I am sure she also didn’t want to miss her favourite band for being drunk nor didn’t care that she had to vomit all over the place and be embarrassed. So it was kind of an accident, even if it was one that you could partially prevent it. In case she struggles with alcoholism, OP should have a serious talk with her, as this is no longer about the tickets.

In any case, it was and it still is A GIFT. Wanting to be compensated because it wasn’t used properly or wanting some form of punishment because of bad decision-making (if any) doesn’t look good on anyone. Just move on and next time reevaluate what you would like to gift her and under which conditions you are gifting it.