Sandy Mission 3-1: Infiltrate Davoi -- NPC not on bridge

Just wanna make a note: the npc may not be on the bridge.
Did that mission like a month ago as 40whm, easy with invis/sneak (not sure if sneak is needed, just in case).
Went to the bridge, stood at the middle, i found orcs at the two ends of the bridge, invis was about to wear off, but the npc did not appear, not even within my sight. The orcs were close, i ain't sure if it's safe to recast at the middle of the bridge. So i just ran past the bridge, turned right into a clear narrow outdoor tunnel (wish you see what i mean). Recast invis there, and the npc was running to and fro there!
Yes, it's quite safe there. Just waited till the npc was running towards me to take off invis and talk to him, passed the cut-scene.Resting mp for warp, it occurs to me that i may have to talk to the npc once again, but soon an orc aggro, so i just warp back with like 50 hp left.
And i proved later that you dont need to talk to that npc again after the cut-scene.