i bought the same issue. This is how I believe it is played:
Fret the G with your index finger, slide up to the 7th fret with your index on the A string, then fret the B on the E string with your middle finger as soon as your index reaches the 7th fret on the A string.
I hope you understood my desription. If you didn't read on:
You reach the 9th measure, the 9th measure has straight eighths of G, fret those Gs' with your index finger, count them as you play, "1..2..3..4..5..6..7..", as soon as you get to "8", slide up to the 7th fret on the A string, when you get to the 7th fret, fret the B on the E string with your middle finger, and play the Bs'.