@Mindtraveller
Man, I feel you, I hope you get this fixed! I would say best bet is to try and get support's attention (either emails or PMs).
Thanks for the encouragement!
I looked up your email address on the forum and matched it to your KS profile on the Vault and fixed that. Let me know if it works.
Many Thanks, it works now! I was able to destroy steam-key, select GOG and successfully redeemed new key. Thank You again.