I have my old doge wallet backup but there's no doge left in them. Do I still get clams?
No. Obviously the wallet.dat has to contain private keys that hold funds. DUH!!! OTHERWISE HOW WILL THEY STEAL YOUR MONEY.
I've imported large Bitcoin and Dogecoin wallets without any problems. The Bitcoin wallet had several hundred BTC in it, and the Dogecoin wallet had over 100 million DOGE. The wallets weren't encrypted. Nothing was stolen.
That's pretty conclusive proof to me that the client is legit.