Hope all is well, Mike! Sorry about the dropped insulin... I've been there! I think you should keep using it, but if you start noticing wonky numbers, I'd replace. Sorry about the long streak of work, but understand the need for overtime! Hope you're able to get buddy to the vet soon! I was looking at google... if VCA doesn't call you back timely, it looks like there are a couple other vets who state on their websites that they have an interest in dermatology... maybe you could try one of those?
Good luck! Hope you're able to get some rest over the next 9 days!