t Rav Gestetner wrote in his nullification of the seruv where he strongly attacks the language of the fourth paragraph for too strongly criticizing the beis din of Machon l'Hora'ah and by inference - the gedolim who agreed with the seruv.
In fact this fourth paragraph makes little sense taken in isolation from the context of the rest of the letter. Consequently because ignored the context of the rest of the document he ended up mistranslating "gate of fraud" rather than "gate for those who are tormented by the words of others." In fact the fourth paragraph follows logically from the preceding paragraphs
Let's go back to the beginning paragraphs. First paragraph: Rav Weiss (the husband) received a summons from Machon l'Hora'ah at the instigation of his wife who is in the middle of a suit in secular court against him. Rav Gestetner explains that according to the halacha the husband is not required to go at the same time to beis din until she pays him for the expenses incurred in secular court... Nevertheless the husband acted beyond what he was required to do and responded to the summons and informed Machon l'Hora'ah that he was prepared to participate in a din Torah with his wife and specified two dayanim who were prepared to judge for his side[and thus he responded correctly according to halacha]. Second Paragraph:In spite of this compliance ,Machon l'Hora'ah responded as if he had ignored their summons and reversed what Rav Gestetner understood to be the facts of the case and claimed that the husband - and not the wife had initiated the lawsuit in secular court. Based on what Rav Gestetner claims were these false claims the beis din issued an invalid seruv which publicly slandered Rav Weiss - despite his total innocence of these claims and he had fully complied with every halachic requirement of the original summons. Rav Gestetner lamented the injustice done to the husband. Third paragraph: Rav Gestetner states that he has the obligation from lo ta'amod" to forcefully defend Rav Weiss and declare that he is a kosher Jew who has in fact complied with the demands of the beis din - beyond that required by the halacha. Consequently Rav Gestetner asserted that there is absolutely no basis for issuing a seruv - which by definition is an assertion that there was a failure to comply with beis din. Thus the issuing of the seruv constitutes slander and therefore the seruv by definition can have absolutely no validity and is null and void.
It is in this context of declaring that Rav Weiss has been unjustly subjected to public disgrace and ridicule based on false charges that Rav Gestetener wrote the fourth paragraph. It is simply a collection of statements of Chazal regarding the consequence of those who embarrass and torment other Jews with words. This includes 1) malbin pnei chaveiro - extreme embarrassment, 2) slander which Chazal say causes loss of Olam HaBah. 3) that they are deserving of nidoi since they are placing an innocent man in nidoi (seruv). 5) He notes that Chazal also say that all gates to Heaven are blocked except from those who cry out because of being tormented by words and these victims are answered immediately.
In sum - there really isn't anything unusual about Rav Gestetner's nullification of the seruv issued by Machon l'Hora'ah. The seruv is issued for failure to comply with beis din's summons - and in fact Rav Gestetner says that there was more than full compliance. The language that is upset about - are simply citation from Chazal. An additional point is that Rav Gestetner - despite claims - is not a one man beis din. There are in fact other dayanim.