Melita,
well yes, you can "georeference" the CAD, much like you would with an image.
But, I think, first choice would be to get to the truth. Especially regarding the underlying datum.
If that step proves to be impossible, then, yes, go ahead.
I have Margaret Maher's book thank you.
Also, done lots of work fiddling with RSO etc etc.
Cheers, Neil