I still suspect an OF will beat out Hall but even if they don't, Bohm, Castellanos and Hoskins and JT will all DH too. But as much as I think Nick should - and will - be the full-time DH in the long run (with Schwarber in the mix as well if they want to throw Nick into LF once or twice a week) I think they'll also prefer to mix and match all season.
And of course we still don't even know how much Bryce will play RF.
If Castellanos's bat returns, of course, he can play wherever and still be bad in the field. If it doesn't return, he can't even DH!