Devastating Help

I let my BF water my dome on Wed to "help" me while I was milking the goats. He didn't double check the door was closed and for 3 days at 0 temps my plants were exposed. This is my banana tree. I had to cut it back. I'm hoping someone can tell me by looking at it if I need to cut further? I'm hoping not but I will do what I must to save it.