The timing of the few prominent notes in that intro are similar to the George Harrison tune, but the notes themselves as well as supporting elements are different, as is the overall percussion.

Unfortunately, while I feel it's not infringing, it is debatable enough to be a problem. "few note" cases like this tend to be painful and should be avoided. I would put that right on his musician friend.

Since the bell appears to be ringing at the school of hard knocks...

Given how YT works at present, this guy should immediately produce his music elements himself, as an original work, in tandem with a musician.

Validate that shit, and then move to using that imaging from here on out.

While that is in progress, definitely counter claim every single one. Gotta be someone in the family, or a friend, able to help. Just knock them out.

Make lots of noise about the whole mess too, including the production of original music, complete with behind the scenes videos that substantiate the originality, as well as inform and transition people to the new branding.

It's possible to move past this, and the creator absolutely should.

It's also reasonable to expect better.