Failing that, if you're familiar with Python/Command line stuff, then I'd recommend "PyWallet", it definitely has a "dumpwallet" command that will extract everything from your wallet.dat. It does not require bitcoind to be synced... in fact, it doesn't require bitcoind/bitcoin-qt at all... just your wallet.dat file
Download here: https://github.com/jackjack-jj/pywallet
BitcoinTalk Thread here: https://bitcointalksearch.org/topic/pywallet-22-manage-your-wallet-update-required-34028
I'll look at getting a vintage copy of PyWallet since I'm sure the wallet format on my file is way older than it's expecting.
Another option is to build on your computer another copy of Core, using a pruned database, then dumpprivatekeys. That would be pretty quick to load.