This level of the temple us where most looters would get stuck. It's a great place to have cultists find the party or for them to encounter competing delvers. I think my players found some straggling hirelings from their rivals who couldn't find their way down to warn the main party.
https://mindweaverpg.wordpress.com/2020/12/17/the-buried-dragon-temple-level-3/
The party ended up getting a little sidetracked by a whole nest of ogres.
#playreport
https://mindweaverpg.wordpress.com/2023/06/30/play-report-kotb-barrier-march-session-52-surprise-ogres/
Searching for more information about the lay of the land around the bugbear crag, the party ends up ambushing a patrol, but when the ambush doesn't get surprise, the battle is far more even than intended.