The spell is supposed to only target a "willing creature", which I guess, Larian decided to consider them not to be willing creatures?
You are absolutely right, as long as they are enchanted, they would not be willing

Just as Owlbear is not a Beast ...
And we can talk to it ... aswell as (based on Game Awards teaser) transform to it ...
I would dare to say that if there is something that dont bother Larian much is rule restrictions.
