I wouldn't worry about that. Such thinking would open the most dangerous doors - any bid'at can now be easily introduced into religion on the excuse that maybe the hadith which recommend it are lost. It is Allah's responsibility to make sure that the complete religion reaches us. Hadith al thaqalayn guarantees it.
It means the same thing to me. I can rephrase the question then: Is there any hadith that says that Shias will survive directly as a result of the acts of their azadari? In fact religion can be destroyed if f bid'ah is introduced in the name of azadari. Refer to the article: https://ahlulbaytmission.org/2019/08/29/dangers-of-bidah/
امام على عليه السلام : ما هَدمَ الدِّينَ مثلُ البِدع
Imam Ali (عليه السلام) said: Nothing destroys religion like the innovations. [Bihar al-Anwar, v. 78, p. 92, no. 98]
رسولُ الله صلى الله عليه وآله : من أتى ذا بدْعةٍ فعطَّمهُ فإنَّما يَسْعى في هَدْمِ الإسلام
Rasool Allah (s) said: If one comes across an innovation and appreciates it (sides with it), he has assisted in the demolition of Al Islam.
[Al Kafi V 1 – The Book Of Intellect and Ignorance CH 19 H 3]
There is no way to find out if a scholar is corrupt or not if you don't demand proof from him from hadith.
There are no hadith which encourage either men or women to wear black as a sign of mourning. However, we are concerned more with the inner dress (libaas) than the outer coverings like cloak, blanket, chador, turban etc. As there are hadith which allow black cloaks and turbans.