Raster spawn question

[Dreads]

I guess this is a monk related question
The Idol is the only piece I have left to get.

Just wanted to know if there any strategy for this spawn. I read on allakhazam about despawn times and in game clock spawn time stuff and all that. Seeing if anyone could explain that or knew how it worked on P1999

Also what level is that camp soloable at without too much risk.

Thanks in advance