If macOS Parental Controls keep blocking allowed apps (both allowed through the checklist in System Preferences and through manually approving via password), deleting the account and recreating it may not be enough to fix the glitch. Instead, try recreating an account with a new name.

I’ve found Santa to block things more reliably (or not to block things you’ve allowed). You can block by certificate or (for Apple applications you’d need to do this), block by binary.