That's a Royal Malawane vehicle, logo on the back of trackers seat.
Pretty common in private lodges operating western Kruger to get close to game. They often have repeat sightings with the same individuals and the guides and trackers know who to avoid and comfort zone.
They already had that bull displaying dominance with the trunk laying over a tusk. Hanging around close I feel is not the greatest choice in guiding just to get a client a show.
Probably has a rifle cased in the vehicle, that's required for some properties. I know it is for the Sabi Sands, but the chances to actually stop a charge would be miniscule at best. Guide is going to depend on driving skills more than anything.