Actually, about 6 runs. Doing slayer cleanup on a L10 toon, find out that he hadn't been to TBC yet. Loaded up and took the ferry.
First run went well, recalled, talked to the barkeep, sold, repaired, refreshed.
Second run went ok, but I noticed that occasionally, a single creature would warp to a new spot. I've seen mobs, guildies, etc all warp around with network lag, but never a single critter.
Recalled, tried to talk to the barkeep again. I got the dialog that asks if you want to trade, I click trade, the windows goes away and he ignores me. It looked like there were two of him there, on top of each other. If I clicked on the "out of phase" barkeep, I got invalid target.
Reset the instance, made another run, recalled back, same thing. Barkeep won't talk to me past the initial dialog.
On one of the runs, the kobold Admiral appeared, we started fighting, he warped underground, and re-appeared at his spawn point fully healed. The rest of the mob behaved normally.
It seemed like the more runs I made, the worse the critter warping got. I was running solo with a cleric hire, and I didn't notice either of us warping around. Again, when that happened, it was only a single character at a time.
I finally got all 3 checkmarks, the barkeep still won't talk to me, so I take the ferry to the harbor and talk to the barkeep in the Leaky Dingy. He won't talk to me either. I checked most of the vendors in the harbor, and none of them wanted to trade.
Logged out and back in, now they want to trade.