2000 passat no speedometer

I was told by dealer that the cluster needs to be replaced and also an engine speed sensor. I installed a used cluster and now still have no speedometer working, no tach,airbag light now on, abs light now on and oil light now on. It's possible that i got a bum cluster from this guy but he said it was working when taken out.
My question:
If i buy a new cluster from a dealer and this is still happening what do i check then???
Does the bad engine speed sensor have anything to do with speedometer???