I am so sorry OP. This man has been awful. Not only has he violated you in the most appalling, public way, but solely for his own benefit he has also deleted his activity, making it much more difficult for you to track down pictures of you and get them removed.
I am not surprised that you are still thinking about him, and how to keep the family together until your holiday, as a wife and mother that is the way you have been thinking and behaving for years and it’s very hard to undo immediately.
However, I think in your case I would be prioritising the removal of the pictures without delay as the longer they are up, the harder it will be to do this. First off tell your husband you want him to hand over his laptop and detail everything he has done or you will go to the police? Take his laptop immediately to a specialist who will help you find, document and take down what they can and keep all the evidence and the money you have spent for any future divorce / settlement. Your husband should pay.
Second, you should tell your husband he must leave the house to give you space to think this through. This is really vital. It will help you to separate mentally, your interests and his own interests (which he is quite capable of looking out for, and clearly doesn’t need your help). You need to focus on your interests and your children’s interests. These come first OP, and your children’s interests are not served by staying with a man who posts identifiable images of their mother on sex websites.
Third, can you take someone else on your skiing holiday instead? … your mother, a friend, even a nanny with skiing/holiday experience who you can hire temporarily? I know it’s nice to imagine that you can all go together happily, but this man is not your husband any more, he is your abuser and for your own mental health and self respect, you need to get away from him.
He has done things that are illegal, unacceptable and abhorrent in the eyes of everyone. This gives you a strong hand going forward in any separation / negotiation, so don’t weaken and give that hand away. Use it to get yourself a clean break, to get your boys away from him and his vile influence and to demonstrate to your boys that you are strong and will not put up with such abuse.
If, at any point he refuses to do what is best for you and the children, tell him you will go to the police and his family and social circle with your file of evidence and that this will ruin his life.
I guess it will be incredibly difficult and mourning the loss of your partner, your relationship and the father of your children will be immensely hard, but you are obviously a strong, caring and thoughtful woman and you deserve to give yourself much better.