There is dry and then there is sober.
They are two different things. There are people I have met at AA meetings who have spoke of not drinking for years but they labeled themselves a dry drunk. Meaning they did not drink alcohol but they still carried all the baggage which in turn drove them to drink again.
As deeker said many jails have AA meetings but some have no programs at all. Maybe you can supply her with some reading material to help her decide if she is an alcoholic and if so, does she want to quit.
Only she can decide if she wants to. Many people do want to but don't have the tools to do so. At this point you can supply her with the tools but only she can make the decision.
I know it is hard, I have a 22 year old daughter myself, but we cannot fix their lives for them. They have to choose to do that on their own, but knowing that you support them is a big part of that.
The fact that she would not admit fault now does not mean she will not later down the road. One of the hardest things to do in life is to admit we were wrong or made a mistake.
The fact that she admitted she has a drink problem is a big step. That is a positive thing.
Good luck and I wish you both the best!