Speaking as someone who was once forced to put a server (not a DC, fortunately) in an unairconditioned closet with the door tied open, a hole in the ceiling through which one could see sky, and foot traffic walking by, I'm curious as to how insecure the location is. If they can hoist your server onto a shoulder and walk out in the middle of the day, there's not a lot you can do.
It looks like you're wanting suggestions like Spencer's--and those are all good--but I think that, rather than a technical solution, you need to either convince management to use a RODC or convince management to put the DC somewhere more secure. Perhaps this presentation from DefCon 21 will help:
So You Think Your Domain Controller is Secure?
JUSTIN HENDRICKS SECURITY ENGINEER, MICROSOFT
Domain Controllers are the crown jewels of an organization. Once they
fall, everything in the domain falls . Organizations go to great
lengths to secure their domain controllers, however they often fail to
properly secure the software used to manage these servers.
This presentation will cover unconventional methods for gaining domain
admin by abusing commonly used management software that organizations
deploy and use.
Justin Hendricks works on the Office 365 security team where he is
involved in red teaming, penetration testing, security research, code
review and tool development.