How can you know what will be? It is very simple, usually, u can`t.

What's the point of listing games with no copies available?

Probably as a placeholder for more incoming keys. Usually Prime keys trickle in until expiry, so BenKii might just be keeping them there for convenience.

Mostly convenience for me since I keep getting donations for them. If donations dry up then I'll remove them in a few days.

Can see someone not noticing the zero and requesting. Tiny issue, especially since they're daggered and therefore not a matter of choosing between them and something else, but for ease of browsing, may move them to the bottom of the list, as in below the link to other available titles, or if you want to keep them in the proper category then under what's still available and with a delimiter. Like:

Expiring Temp Freebies:
The Elder Scrolls I: Arena + II: Daggerfall (x2) [Expires Mar 13, 2025] !!!NO FORUM ACTIVITY REQUIRED!!!
===== PLACEHOLDERS =====
LEGO Star Wars III: The Clone Wars (x0) [Expires June 7th 2024]
Tomb Raider: Game of the Year Edition (x0) [Expires June 8th 2024]