All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
First of all, before answering the first question, we would like to say some facts:
Firstly: The scholars have stated that there is no period of time except that there is a Mujtahid [a person making Ijtihaad, i.e. the juristic opinion on matters which are not specified in the Quran and the Sunnah] who establishes the evidence of the truth for Allaah on His creation, and so, he revives the Sunnah and exterminates the Bid'ah (religious innovation); this is based on the Hadeeth reported by Al-Bukhari and Muslim, that the Prophet, sallallaahu ‘alayhi wa sallam, said: “A group of my nation (the Muslims) will remain fighting for the truth and backing it till the Day of Resurrection…”
Secondly: there are two kinds of Mujtahid: the absolute Mujtahid as is the case of the Four Imaams, and the Mujtahid within the same school of jurisprudence, or in any branch of knowledge, and so on.
There is no doubt that the scholars who are mentioned in the question have played a major role in spreading Islamic knowledge and the Sunnah of the Prophet, sallallaahu ‘alayhi wa sallam. These scholars are renowned for their vast knowledge and the least that can be said about them is that they have done Ijtihaad within their school of jurisprudence. Among these scholars is Shaykh Al-Albaani whom Allaah blessed with the science of Hadeeth and its men (narrators), and he was able to distinguish the Saheeh (authentic) Ahaadeeth from the Dha’eef (weak) ones.
This is with respect to the first question.
As regards the second question, the answer is that you are right in fearing what you mentioned, especially with the lack of piety (among most people) while there are so many reasons of temptations. This requires that a believer should be clever and sagacious, so he should go to places which he predominantly thinks will be free from such matters.
However, at the same time, you should be careful that this matter should not lead you to having whispers.
Allaah Knows best.