Whole thing is G C Em

G / / / | C / Em / |

The way he's playing the riff sounds like he's strumming xxx087 and plucking the B string at the 10th fret then the 8th while the rest of the chord rings.

It looked like he was playing the C chord at the 7th fret with his thumb over the top so he could leave the top E open.

He stays at the 7th fret for the Em as well, also leaving the top E open.

Personally I think it sounds a bit empty playing those shapes without another guitar to give you the lower G in the bass.

If you've got hands big enough for the stretch I'd play

G 3x0007 3x0005 3x0003
C x3555x
Em 022000

It sounds more like the piece as a whole that way.

The other guitarist in the background is arpegiating the C and the Em sometimes and I'd do that every now and again just to make it interesting. Just pluck through the notes of the chords downwards then back up leaving them to ring out. For the Em just pluck the notes 0xx000

I cant be bothered tabbing it out sorry but that should be enough for you to tab it out yourself.