And I just played it and won it.
As I clashed with Guest on 180 level and he started the game I was thinking that it's not looking good for me. Myself - level 162 with Yellow Beard.
But as he opened with T20-T18-T15 I started thinking that maybe not all is lost. As I was on my 'complete White Horse achievement mission', instead of closing numbers I opened 19, 17, and 16. Then he made a second mistake, this time because of lack of skill. Or luck. He closed middle with three darts instead of two. He gained 25 points though, but I felt blood. I quickly closed 20 and started scoring T19. To my horror I hit one S19 so the score looked 76:25 for me. Instead of closing 19 he kept on scoring middles and T15.
I don't remember exactly the rest of the game but I kept on scoring T19 two times leaving third dart for closing 18 and the middle.
I have won this game 475:470.