That is exactly what it is going to happen, because right now the one that has the full rights to that prize money is the girlfriend, and even if I agree that morally half of the prize is his, since it was his idea to buy the tickets and he had the intention to pay for it but his bank app failed, when it comes to the law I do not think he has a leg to stand on, since legally she has the right to get all of the prize money and if she does not want to share it that is her choice, so I think he will lose the lawsuit.
I wished they could have handled this in a friendly manner but not to be. Reading the whole story some questions arises in my mind like
1) Is money more important than any relationship?
2) Are people so greedy for money?
Many people would like to believe themselves to be the kind of person that can put themselves, their family, country and values above all else, but we know better, most people do in fact care way more about the money than anything else, but I really think she is not really considering all the aftereffects this decision will bring her, because even if she could keep all of that money, nothing can be hidden these days, so whenever she desires to start new a relationship with someone else, that person will eventually find out what she did, and most of them will take the decision to give up on her, as it is clear where her priorities are.