Why can't I call a winning hand?

[Talzaroff]

I'm clearly misunderstanding the rules somehow, but I can't see where I'm going wrong. If anyone knows the rules well and could explain to me why I can't use my left neighbor's discarded West Wind to call Ron after I called Riichi last round. As far as I can see, I'm not in Furiten, because I haven't discarded a West Wind or a Red Dragon this game:

https://imgur.com/a/xpG45Fw

BGA automatically drew a blind tile for me at the start of my turn, instead of allowing me to choose the West Wind discarded earlier by my left neighbor. Am I incorrect in thinking that that should be allowed?

[Ringbearer79]

I might see it wrong, but you can only call on a tile that an opponent just discarded. Tiles that are discarded earlier in the hand are gone forever. Unless an opponent would toss a west after you declared riichi you wouldnt be able to go out.

[Talzaroff]

Well, that was the thing I couldn't find in the rules. It does make sense, but since the rules mention "discarded tiles" in general, I assumed I could also take a previously discarded tile. Anyway, thank you for clarifying!
I'm probably pretty screwed with this hand now then

[SRZW]

In fact, a player can only repose to / call the MOST RECENTLY DISCARDED TILE. If nobody repose to a tile, it passes.
This is a rule embedded in almost all Mahjong games. Like many traditional games, most of the related materials only figure out rule variations, but not the basic mechanisms. For authors of these materials, they might think there's no need to mention these 'de facto' rules. This is why we find it's hard to recover a ruleset of a lost game.