Previously, I tried going straight to the hut and only then to Tadeas.
I tested it using the steps you described, and the first issue I noticed is that I tell Tadeas about the ambush even though I haven’t been to the hut yet. I even tried going straight to Tadeas right after accepting the quest, but the ambush dialogue still appears.
You can also refuse the quest and still continue doing it—the quest even gets added to the quest log with the status “in progress.”
I also tested the bribery part, and it doesn’t matter whether I take the money or refuse—it’s the same outcome.