After purchasing Leona and her Iron Solari skin, the skin did not immediately show in the store that it was purchased (though the RP had been deducted). To confirm the purchase, I went to my profile... to find it as pictured in the attachments. Missing champions are completely inaccessible from the profile.
Fiora is there, all the information and stats exist in her profile, but all her art assets are missing. On further inspection, I find that she is not, in fact, in the store, so I cannot confirm that she is playable.
Leaving and reopening the summoner profile blanks out another random assortment of champions. Restarting the client fixes the profile issue, but Fiora remains unavailable.