Could replacing an oil pan cause an oil pump to fail?

We took my car into the Hyundai dealership to get some recall work done-
change oil pan.  When I drove it home, my oil light was flickering.  The
paperwork indicated the mechanic had noticed the light as well.  They
diagnosed it and at first said I needed a new engine.  I told them I had that
replaced by Hyundai last year. Then they said the oil pump. It will cost about
$2700- and my warranty company is giving us a problem as they have in the
past.  Could the recall work to replace my oil pan have caused the problem?  
It frustrates me that when I dropped my car off it didn't have this problem and
now I do and they want me to pay for it. I just want to see if it was just a fluke
that it happened while at the shop or if the replacement could have caused
the problem and they should pay for it or partially pay for it?