My reference article mentions 'Bitcoin Cash' as a trademark. Not sure if that is actually possible; but it is listed as being trademarked.
Hope that helps.
Unfortunately Bitcoin Cash is a trademark.
Source: https://onlinetrademarkattorneys.com/blockchain-bitcoin-trademark/
You can verify yourself in a trademark database.
Regards
Congrats on the Sale!!
This comparable sale might have influenced your sale somehow:
https://www.namepros.com/threads/mike-mann-just-sold-cryptoworld-com-for.1060204/