Rabbi Adam Sinai and Kabbalah

Shalom and blessings. 

I have been trying to strengthen myself lately thanks to you and thanks to the classes of Rabbi Adam Sinai, and a question has arisen for me: I understood from Rabbi Adam Sinai that troubles come upon the Jewish people because we do not study the inner Torah of the Baal HaSulam, namely Kabbalah, and that in order to reach complete tikkun there is a need not only to perform mitzvot but also to study Kabbalah. Is this really so? And is he considered a kosher rabbi? I would appreciate your answer, please; this is very important to me.