re(10) Binyan olam was written by Rav Chatzkel Levenstein Zatzal. The fact that Rav Hutner didnt agree with it (allegedly) doesnt cast any doubts on him ch”v. He probably wrote anonimously out of anivus. Same for sefer amalah shel torah written anonimously written by Rav Shlomo Brevda Ztzal
It is just a machlokos in daos and ze veze…
FYI Rav Hutner did the same thing with Rav Moshe Shmuel Shapiro’s sefer on Kesubos which he didn’t like his peice on geirus for hashkafic reasons.
re(13) Rav Geltzeiler in his hakdama to his sefer Kodshei Yehoshua writes of his father in law Rav Dessler and Rav Hutner having a chavrusashaft wit a chabad chasid “Reb Itche Masmid” who taught them both toras chabad over a period of year or so.