It’s right. The opener would be to your right. He posed the double 4, your partner is opposite with the 5/4 and the openers partner to your left with the 4/2. The game goes anti clockwise.

I know this video is 9 years old but I'm just now seeing it in 2021! Thank you for sharing. I'm dying to know, did you write the book and if so what's the name of it? I'd love to read it!

The 5 is the presenter's partner's. In general you want to keep your partner's position open and kill your opponent's since that would snowball your team to victory. But since player 3... the opposing player before you killed his partner's 4 and opening up with a 2 he probably has no 5s. That's because if he had a 5/2 he would've played it then and supported his partner's opener and pressured the video presenter with their team's strong suit.