Go back into the Blitzball menu and see what the prize is, if it’s not Attack Reels, reload. If it is, play and win it.
Once you’ve been in a total of 250 battles with fiends (you should’ve done that by now), play the league and Status Reels should appear randomly, but only if you’ve obtained Attack Reels.
Once you’ve been in a total of 450 battles with fiends (you should’ve done that by now), play the league and Aurochs Reels should appear randomly, but only if you’ve obtained Status Reels.