Pure speculation.
Kalle already signed a deal with Hyundai for 2020 onwards so they are fine leaving Huttunen for others. Tommi has said that he is interested in Kalle but now that he would not be available he wants the 2nd best option (which i dont think huttunen is) for them.

To be honest I don't believe Huttunen is going to Toyota or that Kalle already has a wrc deal but that explains why Wuorela would know anything (jouhki relationship) and why hyundai could leave Huttunen.