Yeah, you're right, I got that character wrong. Should be Shelly or Sherry.
禁じ手 could very well be on the spine; we'd need a scan or someone with the album to make sure, and it seems that both are in fairly short supply. Given how few places there are with information on this album (less than 20 Google hits on all the catalog numbers and "サウンフォコレクション ソールドアウト"), everyone just getting the wrong title from a single bad source seems plausible to me. We may never know.
As an aside, JGML definitely has at least one title wrong for sure: on the
rock edition, it has "サウンフォ" ("saunfo") instead of "サウンド" ("saundo"/"sound").