Welcome to HCM,
Your husband is having CHF and I am sure he is taking all medicines regularly and following advise regarding fluid intake and salt restriction, some times if there are drugs which may cause Insomnia
so please discuss with your treating doctor.
It is not at all good to take alcohol,or MMJ to such patients.
Please do not give any such thing if he was taking alcohol before then it may be due to withdrawal of alcohol.
There are many drugs which can be given for sleep please ask for prescription of anti anxiety
or sedative for short period which should help him.
In fact if his failure improves and he is comfortable without any shortness of breath
he will have good sleep, propped up posture during sleep may also be helpful.
Please take very good care of him.