Help on a J.K. combo?

Combo: https://www.youtube.com/watch?v=NBlFGlxMh6M

At 1:09 , how does he adjust the string (what does he pull using what fingers)? I’ve tried so many times to adjust it while the yo-yo’s in mid-air, but it never works. Everything ends up moving to the left and and I can’t land the trapeze :[

I don’t know, that’s why yoyos are stupid and I hate them.

Anyways, it looked to me like he only dropped the “outer-wrap” on his NTH Index.