I couldn't understand half of what you're saying, sorry...
To "dumpprivkey" for an encrypted wallet you would first have to use the "walletpassphrase" like:
walletpassphrase <passphrase> <timeout>
...where <timeout> specifies how long to keep the decryption key in memory (see:
https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_calls_list)
example: if your passphrase is "tagada", you have to write , in the console :
walletpassphrase tagada 500then type :
dumpprivkey your-bitcoin-adress-herethen it enter...
best regards