Only way I can see Huttunen starting with Hyundai in WRC Finland is:
He gets that car for FREE
Why would Adamo give him car for FREE, considering Suninen´s results 2021 ?

TGR also hires cars and Yaris has been way better in Finland than i20. (remember that Jouhki is/was manager of Jari-Matti)

You are right that everyone knows that he is fast in Finland so for future Spain would be better but
local sponsor wants/pays him to drive in Finland.

I´m very surprised if he enters with Hyundai, it´s Yaris or Rally2 from TGS/Gardemaister (Jouhki was his manager also)