No it didn't ask for key... I already installed this
https://babiato.tech/threads/req-whmcs-8-1-final-not-decoded-null-required.35416/post-364753 with the key provided and it worked.
Now I just added this hostiko-whmcs-8.zip to my WHMCS templates from the folder you got this one
Hostiko_WHMCS_TEMP_UD5.1.zip. I didn't use this one you're trying to install. I fear the virustotal alert so I didn't install it.
As you can see here
Portal Home - DGI Hosting (realcrazydeals.cf) , the installation is fine. I'm just looking for a payment gateway that'll I can embed now to get my clients to buy from me.