Ok, so, before you all go out on eachother, let me say it straight, both sides have flaws, so calmly listen up.
Firstly let's go with the "they did say" side.
Yes and no. There was only said in one place that it will be for Tokens in the World's event, everyone else said "well, it's only logical if you add the bits of pieces together", so except that one bit of info, that 1) no-one who already bought the pass had any reason to look for again and 2) might've been bugged as even when checking after I the High Noon stuff was added, I for one didn't saw it.
So while yes, they did announce it will be for tokens, they never actually specified it will be for Worlds until it was pretty much too late, and even so, at how little code there seems to be in Riot's spaghetti, there are players that haven't saw it because it wasn't there. So despite being announced, it was announced poorly. What many who knew she'd be for tokens expected was something similar to the Akali one, a one month pass between Worlds and Snowdown.
Now, for the "they didn't say" side, I just stated above, it was mentioned, but very poorly and too far in between mention. Those who bought Prestige Points for it, suck it up, it was announced for Tokens, so just refund, or if you can't refund, there's nothing you can do. And yes, I'm on this side as well, as it's a skin I wanted and didn't expect it to be this pass but in a later one.
All in all, both sides are right, it was informed, but way too poorly. So it can go either way, Riot may make up for it one way or another, or they may not. Due to the poor information, spamming a screen shot of the ONLY ONE PLACE where they did mention it's this pass, which again, was bugged for some, just makes you look like a jerk, those who didn't saw the info are in this one case allowed to complain because of the poor information Riot gave. BUT, that goes both ways, it was stated in the past that it's for tokens, some people may have forgotten (raises hand) but it was stated, so those crying "I wanted it for PP" should also just stop, saying it once is fair, the post was months old, and forgetting some aspects isn't the end of the world, but crying it 24/7 makes you look like a sore loser.
The skin is exclusive, so it shouldn't be available like the other PP skins, BUT, due to the poor information, Riot should allow the skin to be purchasable with PP ONLY DURING THE NEXT PASS FOR A SHORT PERIOD. What I mean with that is that it shouldn't be available the whole pass, but just a realistic estimate of the time it takes to gather the 25 PP from the 5 missions, so, say a week, a week and a bit, making it so players who actually had a chance to get it now but spent the points and didn't got a refund, or those who already had a bunch of stored points may be able to get it, but those who were true late comers and have no stored points, (and by late comers I mean "oh, I saw the skin released and I want it now but wasn't interested in passes or Qiyana before at all) shouldn't be able, as it's the same case as now, you came too late with the "I wanted it", you lost it, but players who didn't knew it was this event due to the misinformation should have a small chance to still obtain it.