When I create a new wallet in Coinomi and try to sweep my old BTC private key (BTC since transferred to another address) I get an error - "The private key does not contain any funds".

I'm receiving with Bitcoin Gold and I'm using the WIF PK provided by blockchain.info - this is where the address (not a wallet) is located. I've also confirmed that I have BTG in my wallet using https://btgexplorer.com.

None of the issues detailed here: https://coinomi.freshdesk.com/support/solutions/articles/29000017747-i-can-t-sweep-my-btg-private-key are applicable.

How can I gain access to these coins?