Hi CocoTech,
To clarify, when he tries to open one of the blocked apps, what specific error or message does it give? Also, while simple, after turning off the restrictions ensure the MacBook is restarted.
Should the issue persist from there, ensure Downtime has been turned off as outlined here:
"Turn downtime on or off immediately
- On your Mac, do one of the following:
- If you’re using Family Sharing: Log in to your Mac user account, then make sure you’re signed in with your Apple ID.
- If you aren’t using Family Sharing: Log in to a family member’s Mac user account.
- Choose Apple menu
> System Settings, then click Screen Time
in the sidebar. (You may need to scroll down.) - If you’re using Family Sharing, click the Family Member pop-up menu on the right, then choose a family member.
- Click Downtime, then turn it on or off.
When you turn on downtime for a child, they’re notified that downtime begins in 5 minutes."
Should the issue persist, contact Apple Support directly for assistance.
Take care.