Author Says:

The Imam had told them not to come out of the tents as long as he was alive (Don't believe those who say that the women kept running out every now and then. Never. The Imam had ordered them to remain in the tents as long as he was alive). He had told them that they must not make any untoward utterance which might reduce their reward with God. He had told them that they would find deliverance and that their ultimate end would be a good one, that God will punish their enemies. They did not have the Imam's permission to come out of their tents, and they did not. Husayn ibn Ali's sense of manly honor and their own sense of feminine honor did not permit them to come out.

The Author here also does not quote any narrations and seems to neglect/reject narrations in our books which indicate otherwise.

For sure this is not a fabrication has we have narrations on this in our book. The authenticity of these narrations could surely be researched but is not correct to call this a fabrication.

Read the following narration quoted from 'Maqatil Al-Talibiyyin'

قال حميد: وكأني أنظر إلى امرأة خرجت مسرعة كأنها الشمس الطالعة تنادي: يا حبيباه، يا ابن أخاه، فسألت عنها، فقالوا: هذه زينب بنت علي بن أبي طالب؛ ثم جاءت حتى انكبت عليه فجاءها الحسين فأخذ بيدها إلى الفسطاط، وأقبل إلى ابنه، وأقبل فتيانه إليه فقال: احملوا أخاكم، فحملوه من مصرعه ذلك،

ثم جاء به حتى وضعه بين يدي فسطاطه

Hameed says, "I saw a women coming out and speeding like a rising sun and calling, 'O My Love', 'O the son of my brother'. When asked about her. Replied, "She is Zainab daughter of Ali bin Abi Talib (as). She came and threw herself upon it (the corpse of Ali Akbar (a.s)). Imam Husain (a.s) lifted her head and brought her back to the tents. Then he called out to the youth saying, “Take your brother”. They brought him from the spot of his martyrdom and placed him in front of the tent facing which he had fought.

[Source: Maqatil Al-Talibiyyin Pg. 115, Ibn-e-Aseer Vol. 4, Pg. 33, Tabari Vol. 6 Pg. 256]

This is also quoted in Nafasul Mahmoom by Sheikh Abbas Qummi.

See Nafasul Mahmoom, Sheikh Abbas Qummi, Chapter 18 (Martyrdom of Ali Akbar bin Husain as)

Other scholars have also quoted this incident and hence for sure this is no a fabrication. A Couple of other scholars who have quoted this incident in their books are:

1) Tareekh-ul-Niyaha - Sayed Saleh bin Ibraheem bin Saleh Al-Shehrastani

2) Ma'a Rakaab Al-Husaini min al-Madinah Ilal Madinah - Sheikh Muhammad Jafar Tabasi