Yeah, Vanguards use the same rifle Stockstrike animation early troopers do. Flame Burst's equivalent is Ion Pulse, which looks like a quick burst of electricity from your rifle. Sorta like Pulse Cannon but smaller and brief. Flame Sweep's equivalent is Explosive Surge, which looks like the Vanguard presses a button and sends an explosion in all directions from their armor.
Edit: Not sure how I managed to time that to only one minute after you gave up on the question.