We had teething rings. Worked then worked now. Don’t see why this mom did not try them.
She may have. But for many years whiskey was commonly used and used safely (as in my case, my mom’s case, my husban’s case etc etc etc).
However with that level, it sounds like she wanted the baby to sleep (some women give their babies Benadryl for the same reason which can be abuse as well) rather than just help with the teething.