virtualbox.org

Is there a VirtualBox Remote Management utility for Windows in the works?
Yes, there are a few Linux/Unix based remote management options available...

• code[dot]google[dot]com/p/vboxweb/
  code[dot]google[dot]com/p/phpvirtualbox/
  remotebox[dot]knobgoblin[dot]org[dot]uk/

But (a) I don't want to spin up a VM for this & (b) I'm looking for something easy for my engineers who aren't as comfortable with Linux as I am.

For what it's worth, it's possible to get RemoteBox running on Windows. There are instructions here

http://remotebox.knobgoblin.org.uk/installwindows.cgi

Your engineers may struggle to install it by themselves but it shouldn't be too hard for a sysadmin to install it on their behalf. Once it's installed though, the engineers should be able to use it easily enough.