Have you tried slowing down this video to see and hear what he's doing?

It's been ages since I've been able to write text tab in a forum post, so I'll have to describe some ideas for right-hand picking (finger sequences) leaving it mostly to you to find strings and frets and locations on the neck.

I think most of the time he may be doing a forward roll pattern followed by forward-backward roll. So that's one 8-note pattern followed by another. I could be wrong. And I think he's hitting the 4th string a lot. You can hear the low notes. It's also possible that he's sometimes starting the pattern on a quarter note (which some players interpret as a rest). Whatever you call it, while the 8-note forward roll pattern COULD be:

T - M - T - I - M - T - I - M  (counting 1 and 2 and 3 and 4 and; picking a note each count)

He might be omitting the second hit ("and" after "one") giving the first hit twice the duration:

T - x - T - I - M - T - I - M  (x = count the "and" but pick nothing)

You'll have to trust your ear to decide if you hear a note picked there or not.

The forward-roll pattern might be followed by forward-backward roll:

T - I - M - T - M - I - T - M

A lot of the thumb hits are on the lowest note, usually 4th string. To my ear I'm hearing a lot of  the 7th note picked on low string and the next use of thumb also on the low string.

And it's possible he's playing mostly forward-backward roll over and over.

I would expct he's mising it up. Not doing the same thing every two measures.

There are lots of combinations you can do. They may not be exact, but they'll be good enough.

Anyway, this is a good exercise for demystifying rolling backup and developing the ability to transcribe someone else's playing from slowed done video and audio,

Good luck.

Hey Old Hickory,
Thanks for taking the time to reply.
I’ve slowed the tune down on an app called “Chordify” which I used to figure out the starting descending run on Cherokee Shuffle as played by Bill Keith. That was relatively easy, as it was easier to hear. I was probably being a bit lazy and looking for an easy answer.
I’ll give it another try, thanks.

Glad to have helped. Are you aware you can slow down YouTube videos? Playback speed control is in the gear icon at the bottom of the video window. By slowing down the video you might be able to see occasional picking patterns.

Hey, no I wasn’t aware. Thanks for the tip. ??