Well I like the separate post idea if the script could auto-capture the names and provide them in list format on the 'reply post' itself. As it is a separate post, the host/admin of the game would get all the upvote-value of that post to keep for themselves, while increasing trust and transparency.

So I, for example, would upvote the original game post (per the rules) then would look for the 'reply post' to see if I won, how many others did, etc. And then upvote the 'reply post' as well as a tip for the game admin. A way of saying thanks. I don't think everyone would, but some will.