I am local. There are some straight up rumors out there but and there are some facts being repeated. Keep in mind that the central Missouri area is very "small town." It is not as transient as many communities and there are many families who have lived here and have known each other for five or six generations. For example - anyone in the area who cared to know her name, where she lived, etc. knew it within 24 hours of her arrest.
In addition, there were over 100 people on site assisting with the search. Many more volunteers were turned away. There were people bringing in food, helping at the VFW, etc..
The disadvantage of being "small town" is that everybody knows your business. The advantage is that they will all be there in a nanosecond to help if you need them.
And then you have the families involved. Not just the immediate family, but aunts, uncles, cousins and their close friends. They are going discuss it; they need to discuss it, to process it and grieve. They will discuss among themselves and with others. There are some that are angry that the truth is not getting out and AB's identity is being protected and I'd say this is to be expected.
Take all this together and you'll understand why there are a lot of details in this case that are known. I think there might be a lot of embellishments coming from the high school - but the information I've heard from adults close to the case has stayed pretty consistent.