Since he has no status in Canada (I guess he is out of status after staying more than 6 months in Canada and didn't apply to restore his status), I think inland is the only option.
And if you applied under inland, he needs to stay and live in Canada with you.
Wait. Did he enter less than 6 months ago? If so he's status is visitor. He has status.
You then can apply outland and then he can go back to the DR. And if he has multi entry TRV, he can come back later.
After AOR, he can apply for OWP once he is in Canada. OWP may take a bit of time for approval and then he can work once the OWP is approved.