What do you mean? A customer service representative?
If it's support, he already got the best solutions in this thread, be it 'to export the keys' or 'to fully sync core', they've already got it covered.

It's just OP didn't responded and looks like he prematurely gave up in his last reply.
(I think he doesn't really got a wallet.dat file but the renamed "wallet" source code of Bitcoin Core)