The lower jaw may not be an issue, just make sure it's eating.
I once had a M. melagris hit the sand so hard she broke her lower jaw. She would nibble bits of mysis, which kept her alive for about a year. Then one day she just stopped eating and she quickly became emaciated and literally wasted away to nothing. I found my CUC taking care of the body one day.
I once had a M. melagris hit the sand so hard she broke her lower jaw. She would nibble bits of mysis, which kept her alive for about a year. Then one day she just stopped eating and she quickly became emaciated and literally wasted away to nothing. I found my CUC taking care of the body one day.

