AFAIK, the only sect which has hadith witnesses by Quran its truthfulness, is shia.
"I leave to you the two weighty things; the Book of Allah and my household. You shall not go astray as long as you keep to them. They shall not separate until they shall come to me at the pond (in Paradise)"
Quran witnesses the truthfuness of the hadith above.
[Shakir 5:55] Only Allah is your Vali and His Messenger and those who believe, those who keep up prayers and pay the poor-rate while they bow.
[Shakir 5:56] And whoever takes Allah and His messenger and those who believe for a guardian, then surely the party of Allah are they that shall be triumphant.
All Muslim sects narrated traditions that Imam Ali had given his ring as charity while he was bowing in prayer and Allah praised him for that and revealed this verse.
you can read more in "Life of Imam Ali bin Muhammad Al-Hadi", page 67/201
You mentioned you watched Videos, In this thread I posted a Video you can watch for point 1, for point 2 search youtube for Lecture 03. Lecture 8 for Succession.
I have extreme a doubt in those hadith verses as I beleive they contradict the Quran, and itself. The Prophet Muhammad SAW if he was of true character, could not have said these words.
Allah left us the Quran, not Muhammad. Allah left us the Book of Allah, in that same book Allah states he is the guide and muhammad SAW is not as I have shown in my posts here earlier. He is but a messenger (quite literally in quran as I also referenced).
For these reasons I don't hold these hadith as authentic.
As I mentioned before , why is that necessary? Are the way Jews and Christians pray from their traditions wrong, or how their (our) messengers did? I practice the way others learned who believe they learned it from those who saw the Prophet do it. That is sufficient for me, as how I pray does not dictate my place in hell or heaven, so as long as its Allah who recieves my worship.
Say: “If ye do love Allah, follow me: Allah will love you and forgive you your sins; for Allah is Oft-Forgiving, Most Merciful.” [Qur’an, The Family of Imran, 3:31]
Does the quran mention that the sunna should not be followed through hadith?