Yes, it does take a bit of getting your head around processing birds that you have raised yourself, especially when it was not your intention to raise meat birds but it makes more sense for you to have a meal out of him that someone else get a free meal. If you can wrangle a swap for some hens...
Good luck with that! Most people can't give surplus roosters away let alone trade them for one or more hens! At least as an Orpington he is dual purpose and will make a good chicken dinner for a family.
This is a typical cockerel mating injury. Have you checked your other hens to make sure they are not also harbouring injuries. This is exactly what @coach723 warned might happen. Yes she should recover but it will need cleaning and antibiotic ointment applying on a regular basis and the cockerel...
He may be quite rampant right through this first season, until late summer/autumn when the days get shorter and it is moulting time but the hen saddle should protect the hen from any further damage in the mean time. Her feathers may not grow back in until she moults. Free ranging gives the...