I agree with your vet (though I am not a fan of Banfield). It just takes time. Leave it alone. If redness/swelling increases you MAY have a concern and it is back to the vet you go. You have this picture to refer to so you can make educated comparisons.
Remember, this is somewhat major surgery, albeit common surgery. It takes awhile for things to get back to normal.
Remember, this is somewhat major surgery, albeit common surgery. It takes awhile for things to get back to normal.