Taking a quick look through the spreadsheet, the following titles only have 4 reviews:
Mr. Beaver
Murderworld
Pharos Fidelis
Space Mission: 2045
Your Very Last Words
The following have more than 4 reviews, but only 4 public reviews:
Under the Sea Winds
Pharaohs’ Heir
Kidnapping of a Tokyo Game Developer, The
Imperial Throne
Day in a Hell Corp, A