Zane got neutered today and beyond feeling like crap right now, he's taking it well. Unfortunately I didn't think to lift his leg and look at his surgery site, but when I got home (after the office closed) I noticed his wound was gaping open! I can easily pull it apart with very slight pressure and see 'stuff' inside. Thankfully it's not bleeding or oozing (or maybe not, since that'd flush out bacteria) and he doesn't seem to be upset about any more than most dogs would be, but damn!
There's hardly any inflammation as if he chewed sutures out, I haven't seen him lick it much and he stops when I tell him to, and there's really no evidence of glue anywhere. He went back to the shelter for the surgery, so I'm assuming in the high-volume of todays surgeries he slipped through the cracks. Poor guy has to go back tomorrow and hopefully get stitched up!
Let this be a lesson - always check and make sure things look okay, and ask lots of questions if you're not sure! I feel like an idiot and a jerk because now he's open to infection and has to deal with going back tomorrow.