The fact is that both Jesus and John the Baptist were prophets, with a fulness of the Spirit of Revelation. Both of them could have gotten the complete and perfect Gospel of Christ from God the Father through revelation; and thus, neither one of them would have needed any kind of input or assistance from the Essenes or the Community of Qumran.
Luke 1: 13-17:
13 But the angel said unto him, Fear not, Zacharias: for thy prayer is heard; and thy wife Elisabeth shall bear thee a son, and thou shalt call his name John.
14 And thou shalt have joy and gladness; and many shall rejoice at his birth.
15 For he shall be great in the sight of the Lord, and shall drink neither wine nor strong drink; and he shall be filled with the Holy Ghost, even from his mother's womb.
16 And many of the children of Israel shall he turn to the Lord their God.
17 And he shall go before him in the spirit and power of Elias, to turn the hearts of the fathers to the children, and the disobedient to the wisdom of the just; to make ready a people prepared for the Lord.
John the Baptist had the Holy Ghost, the Spirit of Revelation, from his mother's womb. That is a special spiritual gift, which 99% of us never receive during the whole of our lifetime, the Gift of Prophecy or the calling of a Prophet. John the Baptist had that gift from the womb, which means that he could have restored the Gospel of Christ through revelation from God if called upon to do so.
26 But what went ye out for to see? A prophet? Yea, I say unto you, and much more than a prophet.
27 This is he, of whom it is written, Behold, I send my messenger before thy face, which shall prepare thy way before thee.
28 For I say unto you, Among those that are born of women there is not a greater prophet than John the Baptist: but he that is least in the kingdom of God is greater than he.
29 And all the people that heard him, and the publicans, justified God, being baptized with the baptism of John.
30 But the Pharisees and lawyers rejected the counsel of God against themselves, being not baptized of him.
If you understand the calling and capabilities of a prophet of God, then you just simply know that both Jesus and John had no need whatsoever to get anything from the Essenes or the Community in Qumran.
Does that mean that they never set foot in Qumran? No. I'm just saying that there was no need for either of them to be there, due to their direct connection with God. Like I said in the beginning, I'm having a hard time finding conclusive evidence one way or the other, when it comes to trying to place John the Baptist (or Jesus) in Qumran. It's possible that both of them grew up there; and, it's also possible that neither of them ever went there. That's basically what the different scholarly articles, that I have found so far, are telling me. We just don't know, one way or the other.
What we do know from the scriptures is that both John the Baptist and Jesus had a fulness of the Spirit of Revelation or the Spirit of Prophecy, which means that either one of them could have restored the Gospel of Christ Jehovah in its fulness without any help from anyone else. They could have gotten it all direct from God.