That's a very serious accusation. Any evidence to back this serious accusation?
السلام عليكم ورحمة الله وبركاته
Here are some highlights:
1) The emissaries were more interested in collecting Khums rather than answering religious questions, instead, referring their followers to the "books of narrations."
2) Al-Kulayni, who was a contemporary and was composing a book of narrations, didn't narrate from the emissaries nor did they authenticate his book.
3) The emissaries used to use letters by the handwriting of Hassan al-Askari's son during the lifetime of Muhammad bin Uthman. After his death, the letters stopped being written with that same handwriting. Interesting note, Muhammad bin Uthman announced ibn Rawh as his successor; making it unlikely that Muhammad bin Uthman wasn't in on the con.
4) al-Samari who was the last emissary left without a successor; which from my understanding is considered "illogical" in the 12er school.
5) The author of the article makes that claim that the concept of the emissaries died out because of "the emergence of the Buwayhid Shia dynasty" because the "Buwayhids were now the representatives of the Shia community and their protectors. They will not share their authority with any Imam or representative since only one party can be in control. The heads of the Shia rejoiced when the Buwayhids ascended to authority and decided that the so called 12th Imam must disappear from our lives to please their new masters and thus began the “greater occultation”."
Please, for the love of Allah, the Qur'an, the Messenger صلى الله عليه وسلم and his Ahl al-Bayt, actually address the points brought up and don't go into "whatabouttery" mode.
بارك الله فيك