I would definitely discuss having the vet do the procedure that you want done.... it's your chicken! I know nothing of the cardiac surgery stuff, seems like an odd operation for a chicken. It seems logical to take care of the comb issue first, instead of a more involved surgery. If no improvement then yes, maybe the cardiac procedure. But, that sounds pricey.I can’t 100% be sure what the vet wants to do for the surgery but pretty sure it is to do with the possible cardiac infection they were suggested.
There’s nothing that signals infection to me? I’ve dealt with infections on animals before of the respiratory kind and in wounds and this isn’t showing me any clear signs of infection? I’m seeing constantly moist tissue that is dying as it’s only on the one side ?
But this is in part why I want the vet to do it! They can cauterize it to stop bleeding plus they can do it in a lot cleaner and safer environment than I could provide.