This happened quite a few times to me.. but requests did go out even if confirm screen didn't appear. s8 staff did post regarding this and gifting confirm splash screen, earlier on in forum.. saying they were aware and looking into the matter.. (sorry I don't dare find the post# too much to go through)
Just mentioning.. but players however freely make their own choices. It's useless to send out so many requests as not needed and doesn't help nor guarantees that your delivery system works faster. It will only throw out 686 of your requests anyway and maybe randomly choose only your 'inactive' nbrs, who will never respond.
Best is to memorize who's participating in the event, from your location and awake (like me
) they surely will answer you, as awaiting answers too.