No, that is not what it says, I am afraid. To understand this sentence, one would need to have basic knowledge of how newspaper articles are written in Japan. I shall come back to this point later.
It says that two groups of people do film critiques in Yomiuri Newspaper. ← The main point of the sentence!
Group 1: 土屋好生のような映画評論家 "film critics such as Yoshio Tsuchiya"
Group 2: 記者 "(regular) newspaper reporters"
「署名入り」 means "bylined".
Unlike in some other countries, most Japanese newspaper articles are traditionally written without the names of the reporters. According to the sentence in question, film critiques are always bylined in Yomiuri. This is why it says 「記者が署名入りで」.
It is implying that when a professional film critic does a critique for Yomiuri (if not for other newspapers), it is naturally bylined. Additionally, even when a regular reporter does a film critique, it is also bylined (unlike with the regular articles that s/he usually writes for Yomiuri).
「一本の」 here does not mean much. Think of it as "a" or "one (by one)".