Ari uses his detect evil radar to find the vampire, if it is in range. OoBH enhanced detection ability let’s me recognize a spefic aura that I’ve encountered before (so I can filter out the rest of the mess) and pinpoint its location.
As long as Ari can get a bead on the vamp, I go after it. Pretty confident that between Astrek’s burrowing (assuming the coffin is underground) and Navi’s teleport, we can make it out before the mob makes it way through the lower levels of the Temple.