Law enforcement did believe two people were using that account because of language differences. It's clear they suspected that person could be KAK's father, but it very well could have been Richard Allen.
The issue with the river is that it's right around the time KAK was removed from jail, and it's really close to his house. RA lived some 40 miles away.
That's why I tend to believe there's more of a direct connection here, and KAK kept quiet because by implicating Allen, he was implicating himself.
That's why I think there may be some sort of deal coming.