So, I haven't talked to my daughter yet to get the details, but she took Dudley back to get his stitches out, and when they started to take them out, the incision started bleeding. So, next steps: insert a staple and put him on antibiotics.
Dudley actually had two bumps removed - the vet also removed one on his elbow that behaved like a lipoma, or "fatty tumor" and as far as I know, was not malignant. And damn if that bit of "cosmetic" surgery is the one that hasn't healed properly. Of course, it is right on his elbow, and therefore constantly flexing and under pressure when he rests on it, but still, it looked fine from the outside. It was the elbow that bled - I don't think they even tried to take out the hind leg stitches yet.
I'll give Team Dudley more details when I get a more detailed update; this is just what I got from text messages from the vet's office.
There's no real drama in the update. His elbow didn't heal, so he has a staple and antibiotics. He's ignoring the staple completely. Dudley concluded years ago that humans are weird and do strange, random things to dogs who were just minding their own business, like moving them to new houses and terrifying them with lawnmower guys outside the window.
So inflicting a body piercing on a dog doesn't seem beyond the realm of possibility to Dudley. It's best to pretend it didn't happen.
If it doesn't heal in the next two weeks, I'm not sure what happens next. I'm going to research dog safe vitamin supplements to aid healing.