This is not my part of the sleuthing, granted, but I think you might want to wade through this part carefully when deciding
preseason on sleuthing potential contestants what is a spoiler and what is sleuthing. It gets tricky here. First, you are sleuthing. Second, if you are extremely boxed in preseason to how you can track down your contestants to slueth what is happening, you may find that you don't have the "who" to go with where they are going.
Think about how few or how many contestants you were able to positively identify simply by twitter or facebook. How about by family or friends? Is the number sizable?
If you are going to really limit yourself by saying that you can't preseason sleuth potential contestants by talking with friends and family, then you might want to re-consider the idea of relegating preseason info from family/friends, etc. to spoilers.
You can always say that once the season starts, talking with family/friends, business associates, etc. is a spoiler. However, I think preseason you need help to have something to get you started so that you can sleuth. jmo.

I do recognize, though, that I am primarily in editing, so this is just a suggestion.