So I solved the problem, and thought I’d let everyone know what it was since I’ve been on here for a couple of days now banging my head against a wall.
As it turns out, an ambitious young would-be network technician decided to go ahead and change what switch my office is on in the MDF down the hall. That switch hasn’t been used in forever since it was so unreliable. I can’t even ssh in to it. I put my office back in the appropriate switch and everything works just like it ought to.
As far as I can tell this has been my issue since square one, and I just wanted to come thank everyone for the help and input along the way to this Mad Hatter’s Tea Party of a solution (chaaaaaaange places!).
Thanks again!