It is implied, but there's a line in Rasputin 2 that suggests otherwise. It's about a guardian watching the cabal and Vex fight, when she detects a third power launching a stealth attack - Rasputin. Before Rasputin opens fire is the following [quote][b]The Vex erupt from nothingness[/b] and crash down over the Cabal in formations of golden light. Lightning arcs and snaps and gives birth to marching ranks of bronze warrior hulls. Gun positions thunder back. Tracers sweep the sky and she can feel on her skin the electromagnetic howl of Cabal munitions seeking targets and [b]the prickle of stranger signals that whisper of broken space and bent time.[/b][/quote] So it seems the Vex may not actually be able to erase timelines outside of VoG. They're certainly doing something that 'breaks space and bends time"

Yeah teleporting