How difficult for you all. I wonder if your friend's predominent concern is more about having been found out as a drinker and the possible consequence of having to face up to this? Her husband seems very much in the background but must surely be aware of the situation unless she goes on binges when he is away and stays in control when he is around?
If T hasn't reported it as might be suggested above, she must be feeling personally very torn and professionally,well. Having knowledge as a professional of something in your personal life that is out of order and involves either a friend or family member is mind blowing.
Hopefully, as others have said, if it is reported and unless T tells you,you may never know, she will at least have to confront her behaviour.CSS will not necessarily do anything,they may just record it as nfa.
Just dont be made to be part of the lie.
Best wishes