Bismillah,

The infallible having a dispute with the other infallible and al-Majlisi like all Shia scholars finds that the only escape is Taqqiyah.

The documents:

روضة المتقين في شرح من لا يحضره الفقيه، للمجلسي ج‏3، ص: 44 :
و في الصحيح، عن زرارة قال: كنت قاعدا عند أبي جعفر عليه السلام و ليس عنده غير ابنه جعفر عليه السلام فقال: يا زرارة إن أبا ذر و عثمان تنازعا على عهد رسول الله صلى الله عليه و آله و سلم فقال عثمان كل مال من ذهب أو فضة يدار به و يعمل به فيتجر به ففيه الزكاة إذا حال عليه الحول، فقال أبو ذر (أما- خ ل) ما يتجر به أو دير و عمل به فليس فيه زكاة، إنما الزكاة فيه إذا كان ركازا أو كنزا موضوعا، فإذا حال عليه الحول ففيه الزكاة فاختصما في ذلك إلى رسول الله صلى الله عليه و آله و سلم قال فقال: القول ما قاله أبو ذر،
فقال أبو عبد الله عليه السلام لأبيه عليه السلام، ما تريد إلا أن تخرج مثل هذا فيكف الناس أن يعطفوا على فقرائهم و مساكينهم؟
فقال: إليك عني لا أجد منها بدا

Rawdat al-Muttaqeen fi Sharh man la Yahduruhu al-Faqeeh vo.3 pg.44:

[In the Sahih, from Zurarah that he said: I was sitting with abu Ja’far (as) at his place, and there was no one present except his son Ja’far (as), so he said: “O Zurarah, abu Dharr and ‘Uthman disputed during the days of the Prophet (SAWS), ‘Uthman said: All money from gold or silver that the people use and work with in trade, they must pay Zakat for it if one year passes. abu Dharr replied: The money you work with in trade and such then you must not pay Zakat from it, but if it was stored and unused and one year passes then one must pay its Zakat. So they went to the Prophet (SAWS) to solve their dispute and he told them: the saying of abu Dharr is correct.”
abu ‘Abdullah Ja’far (as) said to his father al-Baqir (as): “Why would you bring something like this up? How will the Muslims have kindness and sympathy for the poor and weak among them?”
al-Baqir (as) replied: “Stay away from me, I found it obligatory!”]

al-Majlisi said in his commentary:

الظاهر أن منازعتهما صلوات الله عليهما كان لإسكات العامة بأن يقولوا إن ابنه نازع معه و لم يقبل منه لأنه ما يقول إلا ما نقل، عن آبائه عن رسول الله صلى الله عليه و آله و سلم عن الله عز و جل. أ.هـ

“What is apparent is that their dispute may peace be upon them was to silence the ‘Amah(Sunnies) so that they may say: He quarreled with him and did not accept from him as he only reports what he heard from his fathers from the Prophet (SAWS) from Allah (swt).”

Comment:

The report says it was only al-Baqir and Zurarah and al-Sadiq in the house, no Sunnies were present so they can silence them, unless they’re taking acting lessons in a theater.

Salam,