Update:
Sly has had quite a bit of trouble eating post surgery this time around. For the first time since all of this started, we've actually had to force feed him Critical Care. Before he would eat it willingly from the syringe or from a bowl, and this time he had to be held while it was syringed into the back of his mouth where he had to chew. He showed plenty of interest in food, but when it came down to actually eating it, he would try, and then open his mouth wide several times as if he was choking, and then walk away. I have the feeling that he may have had an injury inside his mouth, either due to the overgrown molars or perhaps being nicked during surgery.
Either way, after weigh ins this week, Sly has lost 72 grams since last Sunday. Thankfully, this morning his appetite and ability to eat seem to be returning. For the first time post surgery, he has eaten his entire slice of red pepper, albeit in two sittings. He's also had a pair of baby carrots, surprisingly. He's been in his pellets and also in his hay. I don't feel he's out of the woods yet, but he is much improved over the last couple of days.
For anyone reading these updates and may be going through a similar situation with their pig, I cannot stress enough the importance of making sure your pig gets enough to eat. Even with regular force feedings, Sly still lost more weight than I am comfortable with.