My children have lived with the legacy of a gambling addiction and the added impact of their dad being an alcoholic. I naively thought that the things I was putting in place would protect them from the effects of both.
Not so, children pick up on a lot more than we think and the impact is without a doubt damaging. My ex partner who is a CG told me of a few incidents where he had forgotten to pick up his children due to the need to stay in the bookies and indulge his addiction and also financially priorotising his addiction over their needs etc.
I can only tell you what I would do not what I think you should do and that is – I would never discharge my responsibility for my children to someone who is active in their addiction without a fight. I understand your daughter misses her mother, but without being of the age to make an informed decision with all the facts, I think it is fair to say that the responsible adult should be the one making a decision with as far as is possible – their head not their heart. Your daughter cannot possibly know of the capacity of the addiction to damage her, I don’t know what leaving your daughter in a potentially dangerous situation like that would say about you in the eyes of the courts etc, should things go badly wrong, although I get where you are coming from.
With regards to having your wife thrown out of the casino, perhaps you need to do that to satisfy your own need to know that you have done all you can. I do feel that a CG who wishes to gamble however will find a way so it may be fruitless.
I think your wife needs to be facing the consequences of her actions alone, losing a child through wreckless, childish, pathetic priorities is a consequence, financial ruin is a consequence, these are the things unfortunately she may have to experience in order to want to change – harsh as it may sound.
There is nothing to say that arrangements cannot be altered if and when your wife decides to make some changes and turn things around but until that time comes perhaps concentrating on yourself and your daughters emotional stability will be much more rewarding.