Yeah, you can just cast Threatening Shout and War Cry anytime they’re off cooldown.
Also, for running speed stuff like this, the best Leapquake setup is actually to dual wield, and use Gimmershred (better than Doombringer purely because it rolls CDR). That lets you combine Tribes - In-Geom - Messerschmidt, which lets you keep all your skills off cooldown as much as possible. That’s what I’ve been using for speeds up to about GR 100.
Don’t forget that there are plenty of other players that will still want a 3rd conquest this season. If you do happen to find the event, shout out in General chat in-game for people to come help, and see if you can find yourself a nice GoD DH, MS DH, Bell Monk, etc.