For everything users out there, add this line to your everything.ini to get this behavior:
open_path_command2=$exec("C:\Program Files\GPSoftware\Directory Opus\dopusrt.exe" /acmd Go "%1" NEWTAB=findexisting,tofront)
Then if you map a hotkey to your everything main window it will recycle an existing window rather than opening a new one. Haven't figured out how to avoid opening duplicate tabs in an existing Dopus window (ideally it would reuse not only the window but also an exiting tab with the same name).