It might be able to be done by opening another AutoCAD session that is hidden ... only sometimes AutoCAD willl recognize that another session is running and then terminate the new application and open the drawing in the current session. The only way I would be able to tell you to verify this would be to actually try it.
Can you open AutoCAD 2 times on your computer? If so, then you should be able to do it, but the solution would be in VBA unless you could import the various type libraries into VLisp.