He just mentioned that Amelia wanted her mommy to give her a kiss goodnight i.e. she misses Willow. As the winner of sole custody--Michael and Willow are tasked with working out a visitation schedule. If they cannot agree, then the judge will intervene and decide it. I'd love a scene of what Michael says when they ask why they can't see their mother? Wiley asked the day Michael won and he said something vague like "I'm sorry buddy. I don't think we will be seeing mommy for a bit."
Michael knowing full well that their children miss their mother, could easily set up an hour supervised visit at the Q mansion or a park. If he's concerned about her mental state--then meet with Willow first and assess. All he needs to do is set the condition that Drew is not allowed to be present.
He needs to consider the kids' needs here. If he doesn't want an in person visit--then how about a phone call or FaceTime? This isn't rocket science.