How do I claim BTG from blockchain.info?
You seem to be in a hurry. BTG has not launched yet. Wait until the main net is operational and there is a working wallet.
PS: I'm not sure if blockchain.info is even going to support BTG.
Yes Bitcoingold blockchain is still not public, team are privately mining as much as they can before releasing wallets for public. I am quite sure that blockchain.info or any other big wallets, exchanges will never gonna support this shit coin.
Premined, not eligible developers, supported by very few people.