Your friends rush out when they think the Dragon is past and they have enough time to leg it, they're not always right. Judge it yourself and wait until you time yourself as safe, and yeah, use Quen.
For those who have completed the game on Vernon's path, do you want to talk about the major decisions you made at the end of Act 2 and during Act 3?
I didn't let Vernon kill Henselt, as it would serve the Kingslayer's agenda. [I guessed it was Nilfgaard up to it's old tricks]. I saved Anais instead of Triss, and betrothed her to Radovid, thinking that the alliance could only strengthen the North. I let the Dragon live, as a Witcher does not slay Dragons. And finally, after hearing Letho's explanation, and for his past help in tracing the Wild Hunt, I let the Kingslayer go.
Also, Vernon is a BAMF. I can't wait for the sequel to this one, it was an excellent game and I can't wait to resolve the obvious sequel hooks of this one
Yennefer/The Wild Hunt/Nilfgaard's invasion