Sounds like you should be OK. Eight hours isn't enough time
to freeze the soil so as to damage the corm. I have a couple of musa basjoos' that have been exposed to overnight frost and the plants came back. I'm sure some of the experts will add further to this post.

it will most likely come back unless you're too nice to it. Keep it dryer than usual because it doesn't have any leaves. Keep it in a warm place and expect it might take 4-6 weeks before it actually starts growing actively again. They seem to have a delay time before they start growing again after they're frosted, like they're waiting to make sure that the weather has really changed.

Sandy is right on- not too much water! And patience.