I just did 35 minutes in solo normal with inf ammo. I had to wait on ai Jake to open the gate and died. Then on the snowmobile a huge ice rock rolled past me then I hit it and died after it rolled past me, talk about a glitch! I dont see how its possible to beat the mission in 13 minutes, even with a human partner. But I will give it a go.
I got 17'24 on a practice run. It counted thankfully. This speedrun event has been completely ruined however. It was already bad enough that those with the PSN version and a faster HDD were at an advantage, now those who have splitscreen have an even bigger advantage.