Bitaddress definitely didn't work until I converted it. Whatever blockchain.info outputs from 2013 is not a wif key - which is why I had issues. From the dev of the first tool I used "So, if I recall, blockchain.info saved the private keys in BASE58 format, which is totally not standard....What you need is a tool that can convert that base58 format back into hex or actual WIF format. "

I realise this is confusing, its referenced in one comment I found on the internet. The first tool, the one I used to decrypt the wallet says

"Result
Private keys displayed in raw base58 (not wallet import format)."

The output is not recognised by bitaddress, but I recognised the bitcoin address as correct so persevered.